way for that person. for the very latest, let s go to kelly cobiella in london. reporter: police here in london say the investigation is moving on quickly. at a very brisk pace. they are looking for at least one suspect. no names put out there yet. and so far as far as we understand, no arrests. but multiple senior law enforcement officers in the u.s. briefed lby uk authorities say that the uk authorities have identified a suspect behind this bombing. they also say that this improvised explosive device, this homemade bomb had a timer but that the bomb didn t detonate properly. it still spread a flash fire through the subway car at 8:20 in the morning, the height of rush hour, commuters as well as parents and children in the