25/09/2017 7:53 PM AEST | Updated 25/09/2017 8:49 PM AEST

Parsons Green Terror Attack: Seventh Person Arrested

A seventh person has been arrested by detectives investigating the Parsons Green terrorist attack.

A 20-year old man was arrested at an address in Cardiff at approximately 6am on Monday morning, under section 41 of the Terrorism Act. He has been taken to a south London police station where he remains in custody.

The arrests were carried out by officers from the Met’s Counter Terrorism Command, supported by colleagues from the Welsh Extremism and Counter Terrorism Unit (WECTU) and South Wales Police.

ADRIAN DENNIS via Getty Images
Police forensics workers at the scene following the incident at Parsons Green on 15 September 

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

So far, seven people have been arrested as part of the investigation being carried out by the Met’s Counter Terrorism Command; one person has been charged in relation to the attack, three people remain in police custody and three people have been released with no further action.

On Friday Ahmed Hassan, 18, of Sunbury, Surrey, was charged with attempted murder and using the chemical compound TATP to cause an explosion likely to endanger life. 

He appeared at Westminster Magistrates’ Court on Friday, 22 September, where he was remanded in custody to appear at the Old Bailey on Friday, 13 October. Hassan was arrested in Dover, Kent, on Saturday, 16 September.

Along with the 20-year-old man, a 25-year-old man, and a 30-year-old man also remain in police custody under section 41 of the Terrorism Act in connection with the investigation.

A 17-year-old male arrested on Thursday, 21 September was released from police custody with no further action on Friday, 22 September.

Two men – aged 48 and 21 – were released from police custody on Thursday, 21 September, with no further action.

Searches are ongoing at one address in Surrey and one address in Cardiff. Searches at other addresses in Surrey, Hounslow and Newport have all been completed.

The attack on the District Line tube train in West London left 30 people injured.