the police arrested a suspect:
from Comcast.com:
LEEDS, England - Police said Tuesday they were investigating whether four attackers died in last week's London subway and bus bombings and have arrested one person after a series of raids in this northern city with a strong Muslim community.
At least three of the suspected bombers came from the West Yorkshire region, which includes Leeds, said Peter Clarke, head of the Metropolitan Police anti-terrorist branch.
Closed-circuit TV video showed that all four had arrived at King's Cross station by 8:30 a.m. on Thursday, about 20 minutes before the blasts began that killed at least 52 people, Clarke said.
In a Scotland Yard news conference, Clarke said police had "strong forensic and other evidence" that the man who carried a bomb onto a subway train that exploded between the Aldgate and Liverpool Street stations had died in the blast, and they were awaiting confirmation from the coroner. Police were trying to determine whether the other three also died in the explosions.
Police indicated that there had been a breakthrough in their inquiry.
"This investigation is going at great speed," Clarke said.
"The investigation quite early led us to have concerns about the movements and activities of four men, three of whom came from the West Yorkshire area," he said. "We are trying to establish their movements in the run-up to last week's attacks, and specifically to establish if they all died in the explosions."
One of the suspects had been reported missing by his family at 10 a.m. Thursday, and some of his property was found on the double-decker bus in which 13 died, Clarke said.