An 18-year-old man was arrested in Dover Saturday in connection with Friday’s underground bomb attack in London that injured 30 people, according to police.
Dover, south west of England, has a seaport for passenger ferries to French ports such as Calais and Dunkirk.
“The 18-year-old man was arrested by Kent Police in the port area of Dover this morning, Saturday, 16 September, under section 41 of the Terrorism Act,” a metropolitan police statement 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,” Senior National Co-ordinator for Counter Terrorism Policing Neil Basu said.
Police added that they would not release further details for now.
Thirty people sustained mostly flash burn injuries when an improvised explosive device partially exploded in an underground train at the Parsons Green station on the District Line.
The terror threat level in Britain has been raised to the highest level of “critical,” which means a terror attack is imminent.
The upgrade came following a high-level security meeting after Friday’s explosion.
The threat level was last raised to the highest level following the Manchester concert bombing in May, which killed 22, and remained there for several days.
With the terror threat level at critical, British military personnel may assist police in protection duties at key sites such as Buckingham Palace, government and parliament buildings, as well as at important events across the country.