London subway blast: British police arrest 18-year-old man as terror threat level remains critical

Police arrested an 18-year-old man in the port area of Dover on Saturday morning in connection with Friday's terror incident on London's Tube network that injured 30 people.

Analysts said the number of casualties could have been higher if the device had detonated properly - police sources and eyewitness accounts suggested the improvised explosive device did not function as intended. It exploded partially, caused a flash but did not lead to a powerful blast. Initial investigations suggested that it was a "viable" device.

Scotland Yard said the unnamed man was arrested under Section 41 of the Terrorism Act. Britain's terror threat level was raised to 'critical' on Friday evening following a detailed assessment of the situation in an emergency meeting chaired by Prime Minister Theresa May.

The last time the threat level was raised to the highest level was in the aftermath of the Manchester Arena explosion on May 22. The updated level enables the deployment of army at sensitive



locations and installations.

Neil Basu, senior national co-ordinator for counter terrorism policing, said: "We have made a significant arrest in our investigation this morning. Although we are pleased with the progress made, this investigation continues and the threat level remains at critical.

"The public should remain vigilant as our staff, officers and partners continue to work through this complex investigation. We are not, at this time, changing our protective security measures and the steps taken to free up extra armed officers remain in place.

"This arrest will lead to more activity from our officers. For strong investigative reasons we will not give any more details on the man we arrested at this stage."

The Yard said detectives had spoken to 45 witnesses and continued to receive information from the public to the confidential anti-terrorist hotline. The public has sent 77 images and videos to investigators via the UK Police Image Appeal website.