All four failed London bombing suspects and a possible fifth were under arrest last night as the Metropolitan Police warned the threat to the capital "remains, and is very real".
Two of yesterday's arrests followed a dramatic siege in west London which saw police use specialist tactics, thought to have included stun or gas grenades, to force two men to surrender at gunpoint wearing only their underpants.
One of the men identified himself as Muktar Said Ibrahim (27), who is suspected of leaving an explosive device on the number 26 bus in Hackney, east London, on July 21st. With one of the four original suspects previously unnamed, Scotland Yard said the second man gave his name as Ramsi Muhammed. He is reported to be linked to the attempted Oval tube bombing .
Following the arrest of Yasin Hassan Omar (24), in Birmingham on Wednesday in connection with the attempt on Warren Street tube station, yesterday's critical police breakthrough was capped by confirmation that a fourth suspect, Hussain Osman, had been arrested in Rome. Police suspect he was behind the Shepherd's Bush bombing. There were unconfirmed reports last night that Osman was tracked through his mobile phone on a journey through Paris and Milan to his brother's flat in the Italian capital.
Describing him simply as "another man of interest" to the ongoing investigation, deputy assistant commissioner Peter Clarke, the head of the Met's anti-terrorist branch, confirmed that a European arrest warrant had already been issued seeking his return to Britain.
Police were also questioning a third man arrested yesterday in a separate raid on a residential address at Tavistock Crescent in west London.
He may have been responsible for the dumped bomb near Wormwood Scrubs.
Two women were also arrested at gunpoint at Liverpool Street station.
Mr Clarke refused questions following his press statement last night, and did not connect any of the men arrested with any of the specific attempted bombings. "I must be very careful not to say anything which could prejudice the right of any individual to receive a fair trial," he said. And as he thanked the public for its response so far, the assistant commissioner launched an appeal for more information and warned of "more very visible police activity to come".
While the investigation had moved with some speed, Mr Clarke emphasised: "It is still continuing. It is dynamic, complex and wide-ranging. There will be more very visible police activity."
Yesterday saw extraordinary police visibility in scenes almost unprecedented in London's policing history as part of a national manhunt involving an estimated 10,000 members of the police, security services and special forces.
The sound of gunshots and small explosions filled the air as police moved local residents to safety, while snipers and other police officers laid siege to a flat in Peabody Buildings, Dalgarno Gardens, London W10, with two men inside.
Mr Clarke said the two were asked to surrender but failed to do so. "As a result and in order to minimise any potential risk to the public and to the police officers conducting the operation, specialist tactics were used."
One eye-witness said she was inside a block of flats at the time: "They were shouting at him that he needed to come out with his arms up, in just his underwear. He was saying to them 'How do I know when I come out that you're not going to shoot me? I'm scared'."
She added that police advised the man he would not be shot as long as he followed instructions and they knew he was not a risk to the police or public.
Despite the speed and evident success of yesterday's police operations, Mr Clarke warned: "We must not be complacent. The threat remains, and is very real. The public must be watchful and alert."