UK police fear
5th man loose

Bombing suspect Muktar Said Ibrahim (Sky News)

While British police investigating the failed transit bombings have identified two of four men believed responsible, an explosive discovered in a park raises fears a fifth bomber is still at large.

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Investigators "racing against time" to find the culprits of Thursday's botched bombings say the abandoned device found Saturday is similar to the others – made using clear plastic food-storage containers placed in bags or backpacks, according to Peter Clarke, head of the Metropolitan Police anti-terrorist squad.

The bombers fled three subway trains and a bus when their devices failed to fully detonate.

The abandoned bomb was found in the bushes near the scene of the attempted bombing at Shepherd's Bush station.

The attacks came two weeks after bombings that killed 52 people and four suspected suicide bombers on three subway trains and a double-decker bus.

Earlier today, officials confirmed undercover police mistakenly shot dead a Brazilian man at Stockwell Underground station at the time of Thursday's attacks. The officers, who tracked the man in a winter coat from a suspected terrorist hideout, told him repeatedly to stop as he fled into the station and hopped the turnstiles.

Prime Minister Tony Blair apologized for the killing of Jean Charles de Menezes, 27.

The man's family is considering legal action against the police.

"They have to pay for that in many ways, because if they do not, they are going to kill many people," the victim's cousin, Alex Pereira, told BBC News.

Police have identified two suspects as Yasin Hassan Omar, 24, and Muktar Said Ibrahim, 27, also known as Muktar Mohammed Said. No nationalities were disclosed.

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Providing more details about last week's attack, Clarke described how the four bombers fled when they realized they had failed.

The police chief said the suspect at Oval station in south London was "chased from the station by extraordinarily brave members of the public who tried to detain him."

The man then disappeared in the Brixton neighborhood, where police later found his "New York" sweatshirt.

Omar, the suspect tied to the Shepherd's Bush incident, fled the train, Clarke said, probably by jumping through a window and running along the tracks.

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