LONDON • A second man has been arrested over Friday's bombing of a London commuter train that injured 30 people, as Britain downgraded its terrorism alert level from "critical" to "severe" yesterday.
The 21-year-old man was detained under Britain's terrorism laws in the west London suburb of Hounslow just before midnight on Saturday, the London police said in a statement. He has been taken to a south London police station where he remains in custody.
Earlier on Saturday, the police arrested an 18-year-old youth in the departure lounge of Dover port in what they called a "significant" step, and then raided a property in Sunbury, a town near London and about 6km from Hounslow.
The home-made bomb shot flames through a packed train carriage at west London's Parsons Green Tube station during the Friday morning rush hour, but apparently failed to detonate fully.
The police said yesterday that they were searching a residential property in Stanwell, Surrey, close to the perimeter of London's Heathrow Airport, in connection with the Hounslow arrest.
They said the search of the property in Sunbury, also in the county of Surrey next to the capital, was continuing, but there were no safety risks to local residents.
Local media reported that the Sunbury home belongs to a couple who have fostered hundreds of children, including refugees. The BBC said the couple Ronald Jones, 88, and Penelope Jones, 71, had been honoured by Queen Elizabeth for their work with children.
The Islamic State in Iraq and Syria (ISIS) claimed responsibility, as it has for other attacks in Britain this year, including two in London and one at a concert by singer Ariana Grande in Manchester in May.
Interior Minister Amber Rudd said yesterday that the second arrest indicated it was not a "lone-wolf" attack, but there was no evidence ISIS was involved.
"It is inevitable that so-called Islamic State, or Daesh, will reach in and try to claim responsibility. We have no evidence to suggest that yet," she told BBC, using alternative names for ISIS. "But as this unfolds, and as the police do their investigations, we will make sure that we find out exactly how he was radicalised, if we can."
The bomb struck as passengers were travelling towards the centre of the British capital. Some suffered burns and others were hurt in a stampede while trying to escape. Health officials said none was thought to be in a serious condition.
Prime Minister Theresa May put Britain on its highest security level of "critical" late on Friday, meaning another attack might be imminent.
Soldiers and armed police were deployed to strategic locations such as nuclear power plants. On Saturday, armed police patrolled the streets near government departments in Westminster and guarded Premier League football grounds hosting matches.
But the security level was downgraded to "severe" yesterday.
Meanwhile, a London-bound British Airways flight was evacuated at Paris' Charles de Gaulle airport yesterday due to a bomb scare, but was later cleared for take-off.