Witnesses say a van rammed into pedestrians near Finsbury Park Mosque, in north London, just after midnight. One man has been detained. Follow live updates here.
Jeremy Corbyn, the leader of the Labour Party, said he was "totally shocked at the incident" in a statement released on Twitter.
Corbyn represents North Islington in Parliament, the district in which the incident took place.
London Mayor Sadiq Khan said emergency services are investigating a "major incident" at Finsbury Park. This is the second major incident London has seen in less than a week, the first being the deadly fire at Grenfell Tower, which killed dozens of people.
It also comes in the same month as the June 3 terror attack on London Bridge and the nearby Borough Market in which eight people were killed after three men in a van rammed into pedestrians on before going on a stabbing spree.
Muslim Welfare House
The Muslim Council of Britain, an advocacy group for the country's Muslim community, said in a tweet that the incident took place near the Muslim Welfare House, not outside the Finsbury Park Mosque itself.
An account which appears to represent the community center tweeted: "Our main focus right now is to help the victims on scene, but will hopefully have a statement from the owner of the mosque later. Thank you."
The borough of Islington, where both the mosque and welfare house are located, is home to nearly 20,000 Muslims -- or about 9% of its population -- according to data from the 2013 census. The borough's northern part is represented in Parliament by Jeremy Corbyn, the leader of the Labour Party.
Mosque's notorious reputation
Finsbury Park Mosque, which is located near the scene of the incident, was previously a gathering spot for Islamist militants, according to CNN National Security Analyst Peter Bergen.
Abu Hamza al-Masri, the one-eyed Muslim cleric currently serving a life sentence after being found guilty of supporting al Qaeda, used to frequent the mosque before his extradition to the United States.
Police said in 2004 that the mosque premises "have played a role in the recruitment of suspected terrorists and in supporting their activity both here and abroad."
In an effort to rehabilitate the mosque's image and reputation, the mosque's leadership was changed and al-Masri was banned from attending, according to the BBC.
Screaming and Shouting
Cynthia Vanzella witnessed the incident. She told CNN that she was in bed when she heard a lot of people shouting.
"I went by the window and saw loads, loads of people gathering in the corner right in front of my window," she said. "I didn't see exactly what happened. I just saw from this moment when everybody was screaming, shouting and very, very nervous.
The incident in London happened in the final week of Ramadan, the Muslim holy month.
Muslims fast from sunrise to sunset and finish the day with a large feast called Iftar after praying in the evening.
People who saw the aftermath of the incident have told CNN the van hit pedestrians after evening prayers.
June 19, 2017 2:28am BST
TfL Traffic News@TfLTrafficNews
A503 Seven Sisters Rd is now closed N/B at Hornsey Rd & S/B at Rock St due to an emergency services incident. Seek alternative route.
June 19, 2017 5:59am +06
We have sent a number of resources to an incident in Seven Sisters Road. More information will follow when we have it.
News Courtesy: www.cnn.com