attacks does come out pretty quickly. we haven't seen that in this one, but we have seen arrests in birmingham and a couple more on friday. that suggests this could be a broader network. >> it could be, and i think one thing to make note of the fact is that khalid masood himself had a background as a petty criminal. he'd come into contact with law enforcers for other types of non-terror offenses, and the prime minister pointed to out that he had been a peripheral, quote-unquote, character in other terrorist instances. but wasn't picked up which recalls the omar mateen case in the u.s -- paul: right. >> -- where the authorities suspected something but, ultimately, concluded he wasn't a threat. unfortunately, it turned out to be the case. and this just goes to how difficult this new model of terrorism is where it's these people with petty criminal backgrounds radicalized somehow and then with just a car and a knife they can unleash havoc on