in the wake of what happened at the boston marathon, there will definitely be a beefed up police presence. >> no question. let's go to cnn's matthew chance there for us in london. matthew, tell us about the security preparations there. what's being done to keep runners and spectators safe for this race? >> reporter: it was already a big security operation of course. 35,000 people expected to take part in the london marathon here tomorrow on sunday locally. that security operation has been significantly stepped up according to the metropolitan police who are overseeing that. the police here in london. they for instance have taken away all of the garbage cans from the streets through which runners will pass and will deprive any would-be bombers of a place to hide a device of any kind. a big security operation. an increased state of vigilance and the public will see these compelling images coming out of