Teen arrested in bombing on subway

LONDON — Following a fast-moving investigation and manhunt, British police on Saturday arrested an 18-year-old man in connection with an attack the previous day on the London subway, in which at least 30 people were injured and authorities labeled as terrorism.

Authorities said the man was arrested by Kent police in the port area of Dover on the English Channel. Police suspect he might have been seeking a boat out of England.

In addition, armed police raided and searched a house in Sunbury, west of London, on Saturday afternoon. Counterterrorism units were at the scene, and police told reporters the operation was connected to the subway explosion.

A homemade bomb exploded on a London subway train at Parsons Green station Friday morning, sending a scorching blast of flame and smoke through a London subway car.

Home Secretary Amber Rudd said Saturday that it was “good fortune” the improvised explosive device “did so little damage,” but she said that the materials used to build the bomb were too readily available.

“We have to make certain we take all the steps we can to ensure that the sort of materials this man was able to collect become more and more difficult to combine together,” Rudd said.

Deputy Assistant Police Commissioner Neil Basu called the arrest of the teen at the Dover port “significant” but cautioned that the investigation is ongoing.

The man is being held for questioning under the Terrorism Act. “For strong investigative reasons, we will not give any more details on the man we arrested at this stage,” Basu said.

In the town of Sunburyon-Thames, located about 15 miles to the west of central London, residents waited outside of a police cordon on Saturday evening as forensics experts entered a rowhouse on Cavendish Road.

After the bombing, security measures were immediately tightened across London’s vast mass-transit network, and the government described the threat level as critical, meaning another attack could be imminent.

The Islamic State terrorist group asserted responsibility for the explosion. Experts cautioned that the group often seeks credit for attacks it may have only inspired, as well as ones it had nothing to do with.