British Prime Minister Theresa May criticized U.S. President Donald Trump’s response to the attack that took place at a London Underground Station. Veuer’s Sam Berman has the full story.

British police searching for suspects in the blast on a London subway said Saturday that they had made a “significant” arrest by taking a teenager in custody in the port city of Dover.

Scotland Yard said the arrest by Kent police will lead to “more activity” by authorities, indicating they may have leads on additional suspects in Friday’s blast, which injured more than two dozen people.

Closed-circuit images collected after the incident purportedly show the person suspected of planting the device, the BBC reports.

The teenager, arrested in the port city on the English Channel, was being questioned under the Terrorism Act. Dover is a major ferry port for travel between Britain and France.

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The suspect, who was being returned to London for questioning, has not yet been charged or publicly identified, authorities said.

“We have made a significant arrest in our investigation this morning,” Deputy Assistant Police Commissioner Neil Basu said. He warned that the investigation was continuing and that the terrorist threat level remains at “critical,” meaning a government task force that includes the security services believes another attack is imminent.

British Home Secretary Amber Rudd saids it is “much too early” to tell if authorities knew of the suspect in the London subway bombing

Prime Minister Theresa May said raising the threat level Friday to the highest point was a “proportionate and sensible step.”  Police called on the public to “remain vigilant.”