A vehicle rammed into pedestrians near a north London mosque, killing one man and injuring ten others in an incident that police on Monday said was being investigated by counter-terrorism officers.

Eyewitness said the attacker, deliberately targeting worshippers leaving the mosque after midnight, shouted: “I want to kill all Muslims” as he rammed his vehicle into the pedestrians.

The van had swerved towards the people outside the Finsbury Park Mosque just as they began to assist an elderly man, who had collapsed.

“He turned left into the alleyway, and he just drove at people,” eyewitness Abdiqadir Warra told AFP.

Locals then pounced on the attacker and pinned him down while waiting for the police to arrive. As people seized him, the attacker continued to shout "I want to kill all Muslim."

The 48-year-old man was arrested by the police on suspicion of attempted murder.

“One man was pronounced dead at the scene... Eight people injured were taken to three separate hospitals,” police said in a statement, adding that two other people were treated for minor injuries.

Police said the driver had also been taken to hospital and would receive a mental health assessment.

“Due to the nature of this incident, extra policing resources have been deployed in order to reassure communities, especially those observing Ramadan,” the police statement concluded.

“We have been informed that a van has run over worshippers as they left Finsbury Park Mosque. Our prayers are with the victims,” the Muslim Council of Britain (MCB), an umbrella body, said on Twitter.

Harun Khan, the head of the MCB, said the van had “intentionally” run over people leaving night prayers for the holy month of Ramadan.

"From the window, I started hearing a lot of yelling and screeching, a lot of chaos outside. … Everybody was shouting: 'A van’s hit people, a van’s hit people'," one woman who lives opposite the scene told the BBC.

"There was this white van stopped outside Finsbury Park mosque that seemed to have hit people who were coming out after prayers had finished. I didn’t see the attacker himself, although he seems to have been arrested, but I did see the van."

One witness told CNN it was clear that the attacker at Finsbury Park had deliberately targeted Muslims.

"He tried to kill a lot of people so obviously it's a terrorist attack. He targeted Muslims this time," the witness, identified only as Rayan, said.

“We saw lots of people shouting and lots of people injured,” David Robinson, 41, who arrived just after the accident, told AFP.

The London Ambulance Service said: “We have sent a number of ambulance crews, advance paramedics and specialist responses teams to the scene.

“Our priority is to assess the level and nature of injuries and ensure that those most in need are treated first and taken to hospital.”

'Terrible incident'

Prime Minister Theresa May condemned it as a “terrible incident” and said it was being treated “as a potential terrorist attack”.

“I will chair an emergency meeting later this morning. All my thoughts are with the victims, their families and the emergency services on the scene,” she said in a statement on Monday.

Opposition Labour leader Jeremy Corbyn said he was “totally shocked” and had been in touch with mosques and police.

The area is in Corbyn's Islington North constituency.

A helicopter hovered overhead and several emergency vehicles blocked a section of Seven Sisters Road, a busy thoroughfare where the incident happened.

Police, including armed officers, could be seen manning a wide cordon around the area. Others searched the area with sniffer dogs.

A group of Muslim men were praying on the pavement nearby. Traffic was shut down along a one-kilometre section of the road.

The mayor of London, Sadiq Khan, said extra police had been deployed to reassure communities, especially those observing Ramadan, describing the attack as “an assault on all our shared values of tolerance, freedom and respect”.

'Evil violence'

Finsbury Park mosque was once a notorious hub for radicals but has entirely changed in recent years under new management.

Its former imam Abu Hamza was jailed for life in New York on terrorism charges in 2015.

He preached there from 1997 to 2003 before being jailed for inciting violence. He was later extradited to the United States.

In 2015, the mosque was one of around 20 that took part in an open day organised by the MB to promote better understanding of Islam following terrorist attacks in Paris.

Despite the change in leadership and new focus on community relations, the mosque reported it had received a string of threatening emails and letters in the wake of the Paris attacks.

“If this attack is confirmed as a deliberate terrorist attack then this should be classed as an act of terrorism,” said Mohammed Shafiq, head of the Ramadhan Foundation community group.

“The British Muslim community requires all decent people to stand with us against this evil violence,” he said, adding that “rampant Islamophobia has been on the rise for a number of years”.

Cage, a Muslim human rights group, said there had been “an epidemic rise in anti-Muslim hate crimes”.

“We urge all to remain calm and do their utmost not to inflame an already volatile and distressing situation,” it said in a statement.

Spike in anti-Muslim crime

The MCB said Monday's attack was the most violent manifestation of Islamophobia in Britain in recent months and called for extra security at places of worship.

“It appears that a white man in a van intentionally ploughed into a group of worshippers who were already tending to someone who had been taken ill,” the council said in a statement.

The incident follows an attack on June 3 in which three militants wearing fake suicide vests ran over pedestrians and went on a stabbing spree in bars in the London Bridge area.

They killed eight people before being shot dead by police.

London Mayor Sadiq Khan said following that attack that there had been a 40-percent increase in racist incidents in the city and a fivefold increase in the number of anti-Muslim incidents.

On his Facebook page, Khan at the time called on Londoners “to pull together, and send a clear message around the world that our city will never be divided by these hideous individuals who seek to harm us and destroy our way of life”.

Britain has seen two other attacks this year.

On March 22, a man drove a rented car into pedestrians on Westminster Bridge in London and stabbed a police officer guarding the British parliament to death before being shot dead.

Five people were killed in the attack.

On May 22, a suicide bomber blew himself up outside a pop concert in Manchester, killing 22 people.