President Trump has taken to Twitter during previous terror attacks to make the case for tighter restrictions on travel from predominantly Muslim countries.
He added: "There was a mob attempt to hurt him, so we pushed people away from him until he was safely taken by police".
Egyptian-born Hamza - whose hands were blown off by an explosives experiment in Pakistan - controlled the mosque from 1997 to early 2003, and for years after many terror investigations in Britain were traced back to his influence.
He told BBC Radio 4's Today programme: "The way it works is pretty much there are very large spikes or spikes, we call them measurable spikes, after major terrorist incidences, so Islamist extremist incidences create the largest spikes we see". She said her thoughts were with the injured, their loved ones and emergency officials who responded to the incident. He said he had helped tackle the driver and pin him down with others until police arrived.
"During the night, ordinary British citizens were set upon while they were going about their lives, completing their night worship", the Muslim Council said in a statement, adding that "Muslims have endured many incidents of Islamophobia" over the past weeks and months.
Eyewitnesses interviewed by ABC News said people had gathered outside the mosque after prayers when the van drove into them.
The mayor of London, Sadiq Khan, called the incident "a truly horrific terrorist attack on our city, deliberately targeting innocent Londoners" and said he was pleased ministers had called the Cobra meeting.
"He has been taken to hospital, and will be taken into custody once discharged", the Metropolitan Police said in a statement.
A spokesperson for the Zionist Federation condemned the "ugly attack", adding that "terrorism is terrorism whether it comes from the far-right, Islamists or any other form of extremism", urging everyone to "stand together in the fight against hatred". Parents are scared to send their children to evening prayers. "More information will follow when we have it".
"These were the kinds of comments people were yelling out", she said. It has not been associated with radical views for more than a decade.
The mosque's current leaders say they support inter-faith dialogue and want to serve the nearby community in north London, which is located near Emirates Stadium, home of the Arsenal soccer club.
Earlier this month, eight people were killed at London Bridge, some of whom were hit by a van, and others stabbed by the three attackers.
Police have also denied rumours that a knife was involved.
22 May: Suicide bomber Salman Abedi, a 22-year-old British man of Libyan origin, blows himself up outside a pop concert in Manchester.