Investigations into the London Bridge and Borough Market terror attack that claimed seven lives on Saturday, 3 June, have revealed that one of the three suspected assailants was a man of Pakistani origin, who was radicalised after watching YouTube videos of infamous American hate preacher Ahmad Musa Jibril.

Police have not named the slain attacker, but it has emerged that he lived on King's Road, Barking, with his wife and two children. One of his neighbours has also confirmed that he lived there for several years.

Local media reports claimed that the suspect's parents were asylum seekers from Pakistan. The mother was dead, but the father lived with the suspect at the east London address that was raided by London police on Sunday. Police arrested 12 people in multiple raids conducted near the east London address.

Reports also claimed that the suspect had worked at a branch of the fast food chain KFC, but quit two years ago and took up a job with the London Underground, The Daily Telegraph wrote.

The paper reported that counter-terrorism officers in London had secretly recorded a suspected Isis-inspired terror cell, operating in Barking, in May. The group members were found discussing how to use YouTube to plot a van and knife attack in the city.

London Bridge Terror Attack
Armed police stand over what is believed to be a suspect shot at the scene of a terror attack outside Borough MarketGABRIELE SCIOTTO/AFP/Getty Images

It was not immediately clear if the three slain attackers were part of this terror network, but the plot discussed in the recording was similar to what transpired on Saturday night.

According to the recording, one group member was saying that the intended method for the planned attack would be to "use a car as a weapon". The man also boasted that he had radicalised more than a dozen "students" in Barking "wanting to martyr themselves" for their cause.

Narrating the plan, the person reportedly said that the plot would involve driving at pedestrians and then getting out of the vehicle to attack others. "YouTube videos all make it properly easy to do," he added. Another plotter reportedly talked about "getting an automatic [vehicle] so the boys can drive it".

A neighbour of one of the slain attackers confirmed to police that the man had recently enquired with him about where to hire an automatic van.

The Barking man was reported to police twice by a friend and a neighbour regarding his extremist views. The neighbour claimed that she told Barking police two years ago that the man was "brainwashing" her children at a local park. She said she had confronted him after her two children came home and said, "Mummy I want to become a Muslim."

The friend of the suspect also said that he had alerted anti-terror police when he learned that the man was radicalised by watching YouTube videos of Jibril.

Islamist jihadi group Isis has already claimed responsibility for the attacks, but police believe the attackers were only inspired by Isis videos and were not directly in touch with any of the group's leaders.