Five extremists with links to hate preacher Anjem Choudary are facing jail for their part in drumming up support for Islamic State following a major undercover police operation.
A covert officer infiltrated the Luton chapter of the banned group Al-Muhajiroun (ALM) and secretly recorded speeches over 20 months before police swooped to arrest them.
At the meetings, attended by up to 80 people including young children, the group praised IS and urged people to support the terror group and travel to Syria to fight.
In one rant on July 2 2015, Mohammed Choudry, 23, spoke of "40 trucks driving down Oxford Street full of explosives", the Old Bailey was told.
He was heard to tell an invitation-only meeting in the Bedfordshire town: "A wave is coming - either be a part of it or you drown ... Either you like it or you don't like it."
Zaiur Rahman, 39, helped to organise a series of meetings in July 2015 held in a marquee in his back garden and at a nearby Anglican church in Luton.
Following a retrial, Choudry, from Maidenhead, Berkshire, was found guilty of encouraging support for IS, while Rahman, of Ferndale Road, Luton, was convicted of three counts of arranging meetings in support of a banned organisation.
At the earlier trial, three other members of the group - Mohammed Istiak Alamgir, 37, Yousaf Bashir, 36, and Rajib Khan, 38, all from Luton - were convicted of their roles in spreading IS ideology.
The group will be sentenced by Judge Michael Topolski QC on Friday at the Old Bailey.
After they were convicted, the judge told Rahman and Choudry to expect a jail sentence for their support for IS.
He described it as "a vicious terrorist organisation" which had "hijacked and corrupted the principles and practices of an ancient and revered religion for its own ends and purposes".
The convictions came as a result of a Bedfordshire Police investigation into the activities of ALM in Luton in co-operation with the Metropolitan Police.
During the gatherings, Rajib Khan hailed the Charlie Hebdo terror atrocity in Paris while Alamgir collected money for legal fees of convicted terrorist and ALM leader Omar Bakri Muhammed.
Following arrests in December 2015, police seized more than 270 electronic devices and recovered some 500 images and videos, including footage of Rajib Khan and Alamgir eating with Muhammed by a beach.
Bashir was found guilty of one count of addressing a meeting to encourage support for a proscribed organisation.
Khan was found guilty of one count of arranging or assisting in arranging and managing a meeting to support a proscribed organisation and one count of addressing a meeting to encourage support for a proscribed organisation.
Alamgir was found guilty of three counts of addressing a meeting to encourage support for a proscribed organisation.
Among attendees at meetings were Islamic extremists Shazib and Junead Khan, who were also arrested for their activities.
Last May, delivery driver Junead Khan, 25, was jailed for life for plotting to kill a US soldier in the UK, while his uncle, Shazib Khan, 23, was handed an extended sentence of 13 years for his plans to fight in Syria.
Following a separate Old Bailey trial last year, Anjem Choudary, 49, formerly chief spokesman for ALM, was jailed for five-and-a-half years for encouraging support for IS. He has since asked for permission to appeal against his conviction.