we have offered to the french many times for us to deploy british officers onto the beaches — it's not something they feel that they need. where migrants are packed into flimsy, inflatable boats and sent off into the sea. record numbers of migrants are now reaching british shores this way, and the smugglers are always one step ahead. so who's winning the battle in the channel? we're out on patrol to ask why two of the world's richest and most powerful countries can't stop migrants crossing 20 miles of sea. it's four o'clock in the morning, and we're out on patrol with general frantz tavart and his team of gendarmes. he runs a constant patrol of a0 active gendarmes and 90 reservists, paid for by the uk. together with the police, they patrol almost 90 miles of coastline around calais. this area is known as a goldmine for migrants, but tonight, the beaches are empty. it's a sign, says general tavart, that the french patrols are working. the smugglers may be moving away from calais, but the number of migrants reaching britain from northern france has more than doubled this year. geography is on the smugglers�* side — how do you police a long, snaking coastline, covered with trees, dunes, and hundreds of bunkers left over from world war ii? this is the kind of terrain that the patrols here have to police every night. the sand is so fine your boots sink into it. sometimes there isn't even the moon for light. we check one popular hiding place, but the migrants have gone. they often leave in a hurry. clothes, nappies, even lifejackets — these are the things you leave behind. as dawn approaches, general tavart gets a call — something is happened further down the coast. police have caught a group of migrants in inflatable boat. by the time they reach them, the boat is in the water. this, smugglers tell their clients, is when you're safe from the french police. but tonight, the gendarmes wade into the sea and begin to pull the boat back. it's packed with people. it doesn't take long for one man to realise the game is up and jump out. he helps drag the boat back to shore. everyone on board is likely to have paid between one and 3000 euros for the passage. it's late in the season, when fares are cheaper, and poorer migrants tend to travel. not everyone on board seems to have a life jacket. 0ne kicks at the water as he goes. the officer filming says he can hear a baby crying. seconds later, the baby appears, in a bobble hat to dull the cold of the channel crossing. the boat, thought to have been custom—made, is confiscated. the migrants themselves walk away, back to their camps, to try again. that night, french patrols stopped almost 200 migrants from crossing the channel, but three times as many people did make it to the uk. so what would it take to stop them? we've come to the eurotunnel site at coquelles to find out. and again you can see there's another layer of fencing here. this is the third skin of preventative fencing. calais has been drawing migrants for decades, but until 2018, almost none of them tried to cross the channel in small boats. instead, they used to jump on trucks bound for the ferry port, or come here, to the channel tunnel entrance, to hide on trains bound for the uk. hundreds of migrants used to try and break into the tunnel each day. they don't anymore. the problem's not fixed. the problem's contained as far as our terminal is concerned. and that's been done by basically building a — a perimeterfence around the terminal and adding surveillance cameras, motion detectors, infrared, using drones. we've now got over 600 different video surveillance points around the site, and 37km of fencing — high—security fencing around the site, and regular security patrols, and we're working in cooperation with the authorities — police on both sides of the channel. so there's a whole structure, both physical and intelligence—based, that operates to protect this small site. it costs the uk government £65 million to secure the eurotunnel site — that's about £26 million per square mile. it worked. migrants and smugglers shifted to small boats. but doing the same along 100 miles of coastline is virtually impossible. forested dunes complicate video surveillance, and you can't put a fence around france. david, a migrant himself, has sometimes worked for the people smugglers here. he had hoped to earn a place on one of their boats, but says it never happened. "they're greedy," he says, "and there are plenty of passengers who will pay." he's brought me here to show me one of their hiding places. this is where they bring people before they put them in the boat — an old makeshift shelter. above is a field of cows. and david isjust going to show me inside where they store the equipment. it's pretty dark in here. scattered inside is the debris left by previous groups. and, hidden in the floor, undera rock, a dinghy, wrapped in plastic, and ready to inflate. smugglers now often stash the boats separate from their passengers, to stop them being taken if there's a raid by the police. david shows me the route down to the beach. "the smugglers would get wind of a police patrol up to two hours before it reached them," he says. this year, under growing pressure, the uk announced funding to double the number of patrols on french beaches, and increased surveillance. it's spent almost £90 million on securing this coastline in the past few years. but is the investment having any impact? with more than 4000 migrants reaching british shores last month alone, newspaper headlines are screaming their disapproval. dan 0'mahoney is the man appointed by the government to stop it. we can't build a fence around 200km of french beaches, but what we can do is invest in the long—term in really advanced surveillance technology that allows the french boots on the ground to get to the right place at the right time. but it doesn't work — it doesn't work because we've spoken to migrants who say look, they see the french patrols coming two hours before they get there. isn't it time to be straight with the public and say "look, we cannot police the channel this way"? well look, we've been absolutely clear that the ideal outcome is that the migrants and the criminals are stopped before they get anywhere near a beach in france. but that's not happening frequently enough to break the business model. we're investing in that last stage of the journey in france, on the beaches and around the beaches, with the technology, with french law enforcement officers, and it's not working as well as we want it to. we need to get to the stage where it's more likely than not that if you attempt to cross the channel, you will be stopped. french patrols are now stopping more than half the number of boats from crossing, but the number of attempts has mushroomed this year, partly thanks to covid restrictions drying up other transport routes. in the migrant camps, people smuggling networks seem to be flourishing, despite 65 criminal convictions related to small boat crossings and a newjoint intelligence centre set up here last year. hamid — that's not his real name — is one of many new arrivals from afghanistan. he was a soldier in the afghan national army and says he trained with the british forces. we voiced over his words to protect them. if i stayed, the taliban would kill me — and not only me, but my whole family. i went to the embassy and asked them to help me. i said "i worked with you". if you worked just one day for the army, the taliban will kill you — one day — and i'm national army. i worked many years with the americans, with the british, but now i'm scared. what did the british embassy say to you? he said "you must wait for an e—mail. "i will send you an e—mail and then you must come to the intercontinental hotel — the big hotel." i waited, but he did not send it to me. i went to the airport many times but they did not help me. i went back to the embassy but he still didn't help me. then i came by myself to istanbul, then hungary, then paris. i paid 3000 euros from kabul to istanbul. you paid a smuggler? yes, i paid. he took my passport and after three days, he brought my passport, visa, ticket — everything. most of the people i've met here have made contact with a people smuggler within a couple of weeks. some even made it to the uk in that time. hamid had been here a week when we met. he'd just started looking. three days after our interview, i get a message on my phone. hi, lucy. last night i tried by boat — 75 people from dunkirk — but before we put the boat in the sea, the police came and stopped me. when i speak to him, hamid tells me that the police told the migrants to go back to their camps and try again. he also tells me the smugglers had heard he was talking to the bbc and had threatened him, telling him to stop. general tavart says his menjust don't have the resources to detain dozens of migrants. bigger boats with more passengers are one of the ways smugglers have adapted, and it's creating fresh problems for police. have there been times when you have had to let them go because you... with smugglers now using internal waterways to transport boats to the coast, pressure on all sides is growing. over the summer, the home secretary priti patel threatened to withhold more than £50 million of funding for the mission this year, unless france stopped more boats. while on patrol with us, general tavart issued a threat of his own. shared costs are one thing, shared interests and priorities another. france received more than 150,000 asylum claims in 2019. the uk, around 35,000. with relations strained after brexit, how far will france go to stop a small percentage of its migrants who want to leave for the uk? what has happened over the last ten years, every single time there's an issue, we say "ok, we need five more million for this, 5 million for that," but we are not actually really trying to solve the problem, which means actually working together more closely. john—paul mulot, currently working for france's centre—right presidential candidates, used to be the cross—channel envoy for france's northern region in the run—up to brexit. he spent years studying border arrangements there and talking to those on both sides. if you work together, it has to be really a joint force on the ground where in the army, at the moment, we still have, due to the bilateral treaty, we've got a french colonel running, you know, a british, you know, regiment and we've got a british, you know, commander—in—chief somewhere working with the french — the french military. why is it that we cannot have that at the border and have a joint border force, you know, and that would actually tackle illegal migration? unlike at ferry ports, migrants found by british patrols in british waters cannot be returned to france. with smugglers selling their clients unrealistic dreams of life in the uk, reception facilities there are now vastly overstretched. 0njoint patrols, you know, we have offered to the french many times for us to deploy british officers onto the beaches. it's not something they feel that they need or would find helpful, but the offer is always there. we would love to do joint patrols at sea as well. the french have a very strong view about sovereignty and therefore, it's not an avenue they want to explore at the moment. sovereignty is a loaded issue after brexit. we met france's interior minister last weekend as he visited security forces along the coast. after months of criticism that his patrols are letting too many migrants across the channel, he told us that france had not yet received a penny of the £54 million promised by priti patel three months ago. the uk government says you're just not doing enough, you're not really trying. however good the cooperation between forces on the ground, political relations have been strained — and not just by migration. rows over post—brexit fishing licenses and a secret submarine deal in the pacific have stretched diplomatic niceties to breaking point. general tavart can issue orders to his patrols on the ground but it's politicians in paris who issue orders to him. as dawn approaches, we join the unit on their new patrols along france's final frontier. it's their last chance to intercept migrant boats and take them back to france. but the game of cat and mouse is much riskier than on land and unless a migrant boat is in distress, french forces will escort them into british waters, rather than intervene. the uk now says if france won't intercept boats and turn them back, british border police might — if it's safe to do so. over the past two years, at least 14 people are known to have died trying to cross this slim patch of water. constrained by humanitarian risks and political alliances, maritime borders like this are difficult to police — smugglers know that as well as governments do. the battle in the channel today is a story of migrants slipping between the sovereignties of two great nations. a story of david and goliath, where vulnerability brings its own protection and sovereignty sets the limits of national power. hello, there. temperatures are set to climb through the next few days but don't be expecting blue skies and sunshine all the way. in fact, despite the very mild or even warm deals to the weather, we are going to see some outbreaks of rain at times, and it will often be windy, quite an unsettled start to the new week. this is sunday's weather chart, low—pressure waiting in the wings out to the west, that is going to be moving very slowly eastwards over the next few days. and in the shorter term, this wriggling weather front bringing cloud and some outbreaks of rain. as we go through the day, the rain will tend to turn increasingly light and patchy. many areas will stick with a lot of cloud but there will be some sunny spells, the best of that across the far north of scotland. and later in the day, through southern parts of england and parts of wales and into the midlands. top temperatures, if you do see some sunshine down towards the south of wales, 19 degrees, 14 further north there in glasgow. now, as we head through sunday night, quite a lot of cloud around, some spots of rain and drizzle here and there, may some mist and murk as well. and we move on into monday. 0ur area of low pressure continues its very slow journey eastwards. this frontal system set to introduce some outbreaks of rain so we will see a lot of cloud through monday, some outbreaks of showery rain pushing quite erratically eastwards. there could well be some heavy bursts. a little bit of sunshine here and there as well. but the winds will be coming up from the south, quite brisk winds across western areas, but that wind direction is going to be feeding some quite mild air across the uk. 1a degrees for aberdeen, 18 in norwich and in london. the temperatures have further to climb as we get into tuesday. 0ur area of low pressure still trundling slowly eastwards. this wriggling weather front here likely to bring some heavy rain into western areas but the winds coming all the way up from the south bringing very mild or even warm air our way. tuesday is set to be the warmest day of the week ahead. outbreaks of rain, though, moving across western areas. perhaps some drier, brighter conditions at times further east, and given some sunshine, that is where temperatures could get up to 20 or possibly 21 degrees. now, we won't hold onto temperatures as high as that. as we move through tuesday night into wednesday, this cold front will push its way eastwards, outbreaks of rain with that. behind the front, the air will turn cooler. 0ur area of low pressure, by this stage, tracking right on top of the uk. and on the southern flank of that low, there could well be a swathe of gales. uncertainty about where the windiest weather will be but that could cause some disruption. some showers or longer spells of rain, temperatures a little bit down on tuesday's values, 1a to 18 degrees. in those temperatures will fall back even further on thursday. it is likely that any wet weather will be exited southwards. northern winds developing close behind so despite some sunshine, temperatures by thursday will be struggling a little bit, nine degrees in the north, 13 or 1a down towards the south. so, a cooler spell as we head towards the end of next week with these northerly winds in place. now, it looks like that northerly spell of weather won't last all that long but neither will the little ridge of high pressure that accompanies it, so it will be cooler and a bit drier for a time. but later in the week towards the weekend, low—pressure returns and it will start to turn what unsettled once again. temperatures might climb a little bit but we will see some rain at times and the potential for some quite windy weather as well. that's all from me. bye for now. this is bbc news — the headlines at 10:00pm. the bbc understands the man being questioned over the death of mp sir david amess, had been referred a few years ago to the government's prevent scheme — he's been named by whitehall sources as 25—year—old ali harbi ali. tonight in leigh—on—sea, residents gathered for a candlelit vigil, in memory of their mp. side by side in grief — the prime minister and leader of the opposition visit the scene where of yesterday's murder.