Police step up frantic search operation

Raids by armed police and bomb disposal officers continued across London last night at the end of an extraordinary day of violence and tension in the hunt for the bombers.

One man was arrested in Stockwell. He is believed to have been responsible for the Shoreditch bomb. In Harrow Road, west London, relatives of one of the suspects were taken for questioning.

Another suspect, initially thought to be one of the bombing team, was shot dead at Stockwell station in south London, and rounds of CS gas were fired into the home of a suspect during a search. In Birmingham, a man was arrested at Snow Hill station, and it was evacuated and cordoned off. Police said the man had been detained under section 44 of the Terrorism Act and Army bomb disposal experts were examining two suitcases.

As the hunt for the attackers continued last night, detectives were trying to establish links with the terror cell responsible for the 7 July bombings. The two sets of bombers were believed to be part of the same terror network, although their exact connections remained unclear.

The Stockwell arrest was at a flat in Corfe Road belonging to a woman from Somalia. The man taken away was said to have been a regular visitor but did not live there. Ali Abdalla, who lives near the flat, said: "We heard shouting and opened the door and there were police with guns saying, 'Get inside,' and 'Take it off.' The man who was arrested said, 'I'm doing it.' The police shouted, 'If you don't do it you are going to get shot.' The man asked, 'What do you want me to do now?' The police shouted, 'Turn around and get down.' "

However, at least three of the men suspected of attempting to carry out the blasts remained on the run last night. The man shot dead in Stockwell was said to be "directly linked" to the anti-terrorist operation. He had been tracked from the home of one of the suspect bombers and, police feared, was heading to the Underground station to carry out an attack.

Three addresses, at Stockwell, in nearby Brixton and on Harrow Road in west London, had been traced from material discovered in the rucksacks also containing the explosive devices carried by the bombers. Officers engaged in studying CCTV footage of the 7 July bombings were switched to the investigation of the Thursday blasts, and the four bombing suspects were identified and matched with the details discovered in the rucksacks.

Forensic tests done on the bombs, which had all failed to detonate, revealed that the explosives they contained appeared to be similar to the ones used with such devastating effect two weeks ago.

The police breakthrough came at 3am when officers compiled CCTV images of the four bombers. Hours later undercover officers followed a man they believed was involved with the Oval attack from the Stockwell address on to a bus heading for the Tube station.

Specialist armed officers from the Yard's SO19 section, who train with the SAS at their Hereford base, were called in, and the suspect was asked to stop. Instead he was chased into Stockwell Tube station and shot dead.

The sweater worn by the Oval station suspect was later found abandoned at Cowley Road, Brixton.

In the early hours of the afternoon police surrounded the address at Harrow Road. A remote-controlled robot was sent in first, followed by armed officers, who fired six rounds of tear gas. Two women and a teenage boy were seen to be held spreadeagled at gunpoint and driven away by police.

Patricia Osbourne, 32, a television researcher, said one of the women " came around the corner to be confronted by armed police and what appeared to be bomb squad and forensic officers. A policeman with a machine-gun was yelling and pointing his gun. At the end they took away two women in headscarves.I also heard what appeared to be six shots, but that may have been the CS gas they were firing."

Venetia Elphick said police used her home to target the raided house. " They said they were going to release some form of gas, then I heard some gassy noise and shooting out of the window."

Another resident, Kenneth Mulligan, said his house was also used in the police operation. "Police had told me to take my wife and kids to the back of the house and keep calm. Police officers had gone upstairs with their guns.

"I heard five bangs and then the sixth bang was a big one. I don't think it was a bomb, I think they were firing a canister of gas. The police had gas masks on."