The United States says it "strongly condemns" an attack near a London mosque in which a van plowed into worshippers in the early hours of June 19.
State Department spokeswoman Heather Nauert said "the United States strongly condemns last night's attack that appears to have targeted Muslim worshippers in London."
"We extend our sympathies to the families and community of the victims and our hopes for the quick recovery of those wounded,” Nauert said. She called the incident a “terrorist attack.”
Authorities say at least nine people were injured when the vehicle swerved into a group of people as they left prayers at the Muslim Welfare House and the nearby Finsbury Park Mosque in north London.
A man, who had earlier suffered a heart attack, died at the scene, but it was not clear if his death was connected to the van attack. Police said all the victims were Muslim.
The driver -- identified by media as Darren Osborne -- was grabbed at the scene by locals and pinned down until police arrived.
London police say a 47-year-old man has been arrested on suspicion of terror offenses.
"He has further been arrested for the commission, preparation, or instigation of terrorism including murder and attempted murder," Scotland Yard police headquarters said in a statement.
The statement also said that searches were being carried out at a residential address in the Cardiff area in Wales.
Earlier, British Prime Minister Theresa May called the attack a "sickening" attempt to destroy the freedom to worship.
"It was an attack that once again targeted the ordinary and the innocent going about their daily lives, this time British Muslims as they left a mosque after prayers," she said, referring to recent terrorist attacks in Manchester and London.
She added that the attack was "a reminder that terrorism, extremism, and hatred take many forms and our determination to tackle them must be the same, whoever is responsible."
May also said the driver of the van acted alone and that police would provide additional protection needed for mosques.
The Muslim Council of Britain (MCB) said the attack was the most violent manifestation of Islamophobia in Britain in recent months and called for extra security at places of worship.
The MCB said on Twitter that the incident occurred near the Finsbury Park Mosque and that a van "intentionally" hit worshipers leaving the mosque. The council called on the authorities to increase security around mosques.
The MCB said on Twitter that "we have been informed that a van has run over worshipers as they left #FinsburyPark Mosque. Our prayers are with the victims."
The MCB later said on Twitter that the incident occurred outside the Muslim Welfare House, which is near the mosque. The Welfare House, on Seven Sisters Road, provides social, educational, and training services for "marginalized and ethnic communities," according to its website.
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The authorities said the male driver of the van "was found detained by members of the public at the scene and then arrested by police."
The incident occurred during the Muslim holy month of Ramadan, when people attend prayers at night.
The mosque itself gained notoriety for sermons by radical cleric Abu Hamza al-Masri, who was sentenced to life in a U.S. prison in January 2015 after his conviction on terrorism-related charges. The mosque was shut down and reorganized in 2005 and has not been linked to extremist views.
British Home Secretary Amber Rudd says police "immediately" treated the incident outside a London mosque as a suspected terrorist attack.
The mayor of London, Sadiq Khan, said the attack was "an assault on all our shared values of tolerance, freedom, and respect."
Opposition Labour Party leader Jeremy Corbyn, who is the MP for the area, said he was “totally shocked.”
The World Jewish Congress condemned what it described as “the abhorrent and vicious attack carried out against innocent people gathered to worship during the holy month of Ramadan."
Britain has been hit by a series of attacks in recent months, including a van-and-knife attack on London Bridge and a nearby market on June 3 that killed eight people and injured dozens.
On March 22, a man drove a rented car into pedestrians on Westminster Bridge in London and stabbed a policeman to death before being shot dead. Five people were killed in that attack.
On May 22, a suicide bomber killed 22 people at a concert by American pop singer Ariana Grande in Manchester in northern England.
The attacks played a role in campaigning ahead of the June 8 election, with Prime Minister May criticized for overseeing a drop of 20,000 in the number of police officers in England and Wales as home secretary from 2010 to 2016.