Alert after explosions in London

· 3 tube stations and bus affected
· Less serious than July 7 - police
· 'Armed police enter hospital'
Mark Oliver, James Sturcke and agencies
Thursday July 21, 2005

Guardian Unlimited
Terrified passengers were evacuated from London's transport system today after incidents involving explosives at three underground stations and a bus.

Metropolitan Police Commissioner Sir Ian Blair appealed to Londoners to "stay where you are" in what he described as a "very serious incident".

Sir Ian said though the explosions were "smaller than on the last occasion" and the casualties were "very low ... we do not know the implications of all this yet".

The incidents are at Warren Street tube station in central London; Oval, in south London; Shepherd's Bush in west London and on a No 26 bus at the junction of Hackney Road and Columbia Road in Hackney, east London.

Scotland Yard said there had been no reports of injuries, although the British Transport police said one person had been hurt at Warren Street.

Unconfirmed reports suggested that a number of blasts had been caused by either a nail bomb or by dummy blasts caused by detonator caps exploding, unconnected to explosives.

The Met said initial investigations had found "no trace of chemical agents" at Oval or Warren Street.

Some witnesses at Warren Street said they had heard gunshots and seen an assailant running from the scene. Scotland Yard sources said it was unclear if the noise was from gunfire or detonating caps.

Television footage showed that the bus, which had been evacuated, was intact, although there were conflicting reports about whether it had its upper windows blown out. A spokesman for Stagecoach, which operated the service, said the driver had heard a loud bang from the upper deck.

The incidents come two weeks to the day after 56 people were killed when four suicide bombers attacked three tube stations and a bus in the capital.

A passenger on a tube train about to arrive at Warren Street tube station said another passenger had told him there had been an exploding rucksack. He described seeing smoke and dozens of panicking passengers running through the train.

"The train was not far short of Warren Street station when suddenly the doors between my carriage and the next one burst open and dozens of passengers started running through," retired special constable Ivan McCracken told Sky News.

Police cordoned off most of Euston Road, near Warren Street, and officers with sniffer dogs combed the pavement and the surrounding area.

Rows of fire engines lined up outside nearby University College Hospital next to the station and there were unconfirmed reports that armed officers had entered the hospital.

Sky, quoting "unofficial police sources", reported that staff at University College Hospital had been passed an internal memo asking them to look out for a black, possibly Asian man, around 6ft 2ins tall, possibly with wires protruding from a hole in his blue top. They were instructed to call 999 if they saw the man, according to the report.

A hospital spokeswoman confirmed that at police had requested that an email be sent to staff asking them to be on the lookout.

Sosiane Mohellavi, 35, was travelling from Oxford Circus to Walthamstow when she was evacuated from a train at Warren Street.

"I was in the carriage and we smelt smoke - it was like something was burning. Everyone was panicked and people were screaming. We had to pull the alarm. I am still shaking. We pulled into Warren Street and were evacuated. It was horrible," she told the Press Association.

Residents from houses surrounding the affected Shepherd's Bush Underground station were evacuated from their homes, with many waiting behind a police cordon which stretched back some distance from the scene.

Officers had taped off a large section of Wood Lane, close to BBC Television Centre, forcing dozens of residents and shopkeepers out of buildings.

An eyewitness of the incident at the Oval said a man had joined the train carrying a bag.

"He had a black holdall when he boarded the train," he told Sky News. "He put it down and suddenly ran off the train. People tried to stop him but he got away. There was then a noise which sounded like the popping of Champagne corks."

Witnesses to the explosion on a double decker bus in East London said there had been a bang followed by the smell of smoke.

But they said no one appeared to have been injured following the explosion on the number 26 service in Hackney Road.

British Transport police said all of the affected tube stations were being evacuated.

Transport for London confirmed that four lines - the Hammersmith and City, Northern, Bakerloo and Victoria - had been suspended.

A spokesman said: "There is a code amber which means that the trains are being taken to the next station and passengers evacuated to above ground. Police are at all three stations."

Overland services were running as normal and had not been affected, a Network Rail spokesman said

A London Ambulance spokesman said: "We are currently responding with other emergency services to incidents at Warren Street, Shepherd's Bush and Oval ... at this time there are no reports of casualties at any of the scenes."

The spokesman said they were called to Oval at 12.38pm and sent three ambulance vehicles; they were called to Warren Street at 12.45pm and sent five vehicles.

Police appealed for mobile phone images of the incidents. Mobile phone users in the capital were urged today to make only brief, urgent calls to stop the network overloading.

Downing Street said that given the uncertainty over events, the prime minister, Tony Blair, had cancelled a visit to a school in east London this afternoon. He had been due to meet security chiefs to discuss the July 7 attacks later today.

The Metropolitan police have warned of a risk of further attacks.

The London mayor, Ken Livingstone, has cancelled a visit to the Family Assistance Centre set up to help victims of the July 7 blasts in light of the current tube incidents.