LONDON — Without firing a shot, police raiding apartments in London and Rome yesterday rounded up the last of the four suspects from the failed July 21 transit bombings in Britain.
Two of the suspects were arrested in west London, near the upscale Notting Hill neighborhood, during raids by heavily armed police wearing gas masks and lobbing stun grenades.
Video of the arrests broadcast by ITV News/Daily Mail in London showed two men identified as bombing suspects stripped to the waist and emerging at gunpoint on a balcony of an apartment after police apparently fired tear gas inside.
Tracing cell phone calls across Europe, police in Rome arrested Osman Hussain, a naturalized British citizen from Somalia, said Italian Interior Minister Giuseppe Pisanu. Mr. Hussain, who reportedly fled London and stopped in Milan and Bologna en route to the Italian capital, was “the fourth attacker,” he said.
With those arrests, as well as that of Yasin Hassan Omar on Wednesday in the city of Birmingham, authorities believe they have captured all four men whose photos they released after last week’s botched bombings, a police official said.
“We have four people in custody we believe are the images we released,” said the official, who asked not to be identified in accordance with British practice, referring to images taken from closed-circuit TV cameras on July 21.
Another man was arrested in a separate raid in west London, but police did not release any information about him, a Metropolitan Police spokesman said.
So far, about two dozen people have been arrested in connection with the attacks last week in which bombs in backpacks failed to detonate fully on three subway trains and a double-decker bus. Those attacks caused no injuries, unlike the July 7 attacks in London that killed 56 persons, including the four suicide bombers.
The police operation yesterday was carried out in at least two locations in Notting Hill about a quarter-mile apart.
One of those arrested was believed to be Muktar Said Ibrahim, 27, who purportedly tried to blow himself up on a double-decker bus in east London. Mr. Ibrahim, also known as Muktar Mohammed Said, came to Britain in 1990 from Eritrea.
The suspect arrested with him identified himself as Ramzi Mohammed, said Peter Clarke, head of the Metropolitan Police’s anti-terrorist branch. A police official said Mr. Mohammed was the suspect shown wearing a “New York” sweat shirt and believed responsible for the attempted bombing near Oval subway station.
Police also arrested two women at the Liverpool Street train station in central London and evacuated the area. One woman is believed to have been in a line for the Stansted Express, which goes to one of London’s airports, when she was pushed to the ground by police.
The women were arrested at 1:54 p.m., British Transport Police said. The police were searching a number of suspect packages in the station.
The area of yesterday’s raids is near west London’s Little Wormwood Scrubs park, where police on Saturday found a dark backpack containing a fifth bomb connected to the July 21 attack.
An official at the British Embassy in Rome said the arrest was carried out as part of a joint investigation by Rome and Scotland Yard.
An arrest warrant has been issued “and we will be seeking the return of that man to this country under the authorization of that warrant,” said Mr. Clarke.
Mr. Hussain is suspected of targeting a subway train near the Shepherd’s Bush station. He was shown on closed-circuit TV footage wearing a backpack in the Westbourne Park station.
Mr. Omar was arrested during a dramatic raid Wednesday in Birmingham in central England. The 24-year-old Somali citizen with British residency is suspected of attacking a train near the Warren Street station.
Scotland Yard police headquarters declined to comment on the arrest in Zambia of a British man sought in connection with the July 7 bombings.
British investigators reportedly believe Haroon Rashid Aswat, 31, had been in telephone contact with some of the four suicide attackers who carried out the July 7 attacks. Mr. Aswat told investigators he once was a personal guard for Osama bin Laden, Zambian security officials said.
The British Foreign Office said it was seeking access to a Briton reportedly detained in Zambia but would not identify him.