Hate preacher Anjem Choudary dined with Barking London Bridge terrorist at least three times while on bail for drumming up support for Islamic State, but the connection was not investigated by counter-terrorism police.
Khuram Butt, 27, became friends with his "idol" who was the former leader of the banned group ALM before his marriage in December 2013 - and would campaign alongside him and other fanatics, an inquest heard on Wednesday, May 29.
On June 3 2017, Butt and two other extremists launched a van and knife attack on London Bridge and Borough Market which left eight people dead and 48 others injured.
A lawyer for the victims questioned why Choudary was not investigated by counter-terrorism police for encouraging Butt to carry out the atrocity.
Gareth Patterson QC highlighted a report by Hamza Raza who told police Butt had been heavily influenced and "energised" by Choudary.
Mr Raza described his former friend as being "like a lion out of a cage" in the preacher's company.
Butt went to Choudary's Ilford home for dinner at least twice - and the attacker hosted him at his east London home once, the inquest was told.
The father-of-two also met Mizanur Rahman, who was convicted alongside Choudary in 2016 of inviting support for Islamic State.
Mr Patterson said: "So it looks as though Butt was visiting at the home address of Choudary at a time when he was released on bail on suspicion of terrorist offences."
Acting Detective Chief Inspector Wayne Jolley, who investigated the attackers, replied: "Yes, Sir. That would be correct."
Mr Jolley agreed Mr Raza's statement appeared to suggest Choudary had encouraged Butt.
But he said it was "hearsay evidence", adding: "We would look to seek an evidential case before we put it to the Crown Prosecution Service."
"We did not arrest Anjem Choudary during this investigation."
The attacker's sister Haleema Butt also told police he "idolised" Choudary.
The court heard Butt's views were so far "off the scale", his brother-in-law Usman Darr reported him to a counter-terrorism hotline on September 30 2015.
Mr Jolley confirmed that was the only time authorities were alerted by anyone to Butt's increasingly extreme behaviour.
Mr Patterson observed: "When he was openly expressing hatred for this country, his family and friends were not reporting that to anyone, were they."
The inquest continues.
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