Police said the attack happened while a man, who later died, was receiving first aid after being taken ill in Seven Sisters Road.
British Security Minister Ben Wallace said authorities were aware of rising far-right activity, but were not aware of the suspect prior to the attack near a north London mosque.
Witnesses described how the van veered off the road into a crowd of people leaving the area after late-night prayers. "I want to kill Muslims, '" said Rahman.
Ten people were hurt, all Muslims, with eight requiring hospital treatment.
Two of them were in a very serious condition, police said.
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Two neighbouring Tube lines are to be partly suspended into a second day amid safety concerns of debris falling on to the tracks. British officials have ordered a review of other buildings that have had similar renovations.
An elderly man died after the attack.
After being dragged from the van by an angry mob, he was protected by the Imam of the mosque, Mohammed Mahmoud, who ordered people not to attack him, but hand him over to the police.
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A man drives his rented SUV into pedestrians at London's Westminster Bridge, killing four people, then stabs a police officer to death before officers shoot and kill him.
"We don't yet know the full details, but this was clearly a deliberate attack on innocent Londoners, many of whom were finishing prayers during the holy month of Ramadan".
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Varadkar said he would emphasize to May the British and Irish governments must remain impartial in Northern Ireland, as stipulated by the Good Friday Agreement.
Senior politicians have attended the scene of a terror attack targeting Muslims in London.
"The United States stands in solidarity with the United Kingdom in the face of this terrorist attack and emphasizes our shared resolve to counter the plague of terrorism".
She has faced heavy criticism for her response to a fire in a London tower block on Wednesday which killed at least 58 people, and for her record on security after a series of attacks blamed on Islamist militants in recent months.
Prime Minister Theresa May and opposition Labour Party leader Jeremy Corbyn visited the mosque on Monday morning.
"Diverse, welcoming, vibrant, compassionate, confident and determined never to give in to hate".
An aerial view of where the incident occurred in Finsbury Park.
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Perhaps more significant, however, was its report that 64 percent of Americans disapproved of Trump's performance. He dipped down to 43 percent on May 17, in this particular survey , and has been slowly moving back up since.
Its former imam, Abu Hamza al-Masri, was jailed for life in NY on terrorism charges in 2015.