A second man has been arrested in connection with Friday’s attack on a London Tube train. police say.
The 21-year-old man was arrested in Hounslow, west London, on Saturday night on suspicion of a terror offence and is in custody in south London.
An 18-year-old man is being held on suspicion of a terror offence over the Parsons Green explosion, which injured 30 people.
He was arrested at the Port of Dover earlier on Saturday.
The UK terror threat level remains ‘critical’, meaning an attack is expected ‘imminently’.
Police are continuing to search a house in Sunbury-on-Thames in Surrey.
The house belongs to an elderly couple known for fostering hundreds of children, including refugees.
Ronald Jones, 88, and Penelope Jones, 71 were rewarded for their service to children by the Queen, who made them MBEs in 2010.
The couple are said to be staying with friends following the police raid, during which surrounding houses were evacuated.
Friend Alison Griffiths said the couple had an 18-year-old and a 22-year-old staying with them recently.
She described Mr and Mrs Jones as “great pillars of the community”, adding: “They do a job that not many people do.”