Counter-terror police visited the main suspect in the Parsons Green bombing just weeks ago, a neighbour has claimed.

The 18-year-old, understood to be suspected of planting the device on a Tube train, is believed to have been living with foster carers Ronald Jones, 88, and wife Penelope, 71.

Their home was subject to an armed raid on Saturday (September 16) morning and is still behind a huge metal police cordon on the street in Sunbury-on-Thames, Surrey.

Stephen Griffiths, 28, who lives opposite the "lovely couple", said they were visited "multiple times" by police, and added that he thinks their house may have been under surveillance.

"The police were there multiple times over the span of about a month - a few times a week," he told the Press Association.

"They started off as normally dressed cops, then moved up in the police ranks, wearing black uniforms in an undercover car.

"They used to speak to Penny and Ron on the doorstep, but the last couple of times they went in the house.

"You always think foster kids are going to have a bit of trouble, but you don't think terrorism.

"It's crazy to think it's over the road from you."

Forensic officers investigating a property in Cavendish Road

Mr Griffiths said the home was last visited by police between two and three weeks ago, and having witnessed Saturday's raid, he now believes they were counter-terror officers.

"You need to question whether the house was under surveillance," he said.

"I think counter-terror police visited a few weeks ago, and if so, why wasn't something done sooner?"

A Metropolitan Police spokesman said the 18-year-old, who was detained on Saturday morning in the departure area of Dover ferry port, had not been arrested "in the last couple of weeks".

But she could not confirm whether he or the property had been visited by officers recently.

When asked if the 18-year-old was known to police, a Metropolitan Police spokesman said: "I don't believe he was."

He added that he was not aware of any Met officers visiting the address in Sunbury-on-Thames in the weeks before the attack.

The Metropolitan Police said a 21-year-old man was arrested in Hounslow at around 11.50pm on Saturday (September 16).

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

The 18-year-old man was arrested by Kent Police in the port area of Dover on Saturday under section 41 of the Terrorism Act.

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