Police have made a seventh arrest in connection with the London terror attack at Parsons Green Tube station.

A 20-year-old man was detained at an address in Cardiff at around 6am on Monday morning (25 September), police said.

He was arrested under section 41 of the Terrorism Act and remains in custody at a south London police station.

Officers say they are also carrying out a search at an address in Cardiff.

It means seven people have now been arrested by anti-terror police in connection with the Parsons Green attack on 15 September, which saw a crude home-made bomb left on a District Line train on the London Underground.

The device is understood to have failed to properly detonate but still left 30 passengers injured.

One person has so far been charged in relation to the attack, while three people remain in police custody and three others have been released with no further action.

Iraqi orphan Ahmed Hassan, 18, of Sunbury, Surrey, was charged with attempted murder having been arrested in Dover, Kent, the day after the attack. He also faces a charge under the Explosive Substances Act.

He appeared at Westminster Magistrates' Court on Friday (22 September) where he was remanded in custody to appear at the Old Bailey on 13 October.

Along with the 20-year-old man arrested on Monday, two other men – aged 25 and 30 – remain in police custody after being arrested in Newport, Wales, on Tuesday and Wednesday of last week.

A 17-year-old boy arrested on Thursday in Thornton Heath, south London, was released from police custody with no further action the following day, while a 48-year-old man arrested in Newport has also been released.

The final suspect – 21-year-old Yahyah Farroukh – was released with no further action on Thursday.

The Met Police said searches are ongoing at one address in Surrey and one address in Cardiff.

Previous searches at other addresses in Surrey, Hounslow and Newport have all been completed, detectives added.