LONDON — A van ploughed into worshippers near a London mosque yesterday, in what Prime Minister Theresa May described as a sickening, terrorist attack on Muslims, amid fears of retaliation for several recent assaults in the country attributed to Islamist extremists.

Shortly after midnight (UK time), the van rammed into a group of pedestrians near the Finsbury Park Mosque, in North London.

One person died at the scene and at least 10 were wounded, but the authorities said it was not immediately clear if the man died as a result of the attack.

The assault, which the police said was carried out by a 47-year-old white man who was believed to be acting alone, drew condemnation from a broad array of political and religious figures and came at what Mrs May acknowledged was “a difficult time in the life of the city”.

The authorities said that the assailant, identified as Darren Osborne, a father of four living in Cardiff, was not previously known to them in terms of extremism. Osborne was being held on suspicion of terror offences, said Scotland Yard.

Some Muslims and others were asking whether the authorities and media were quick enough to describe the assault as an act of terrorism — although the premier noted the attack had been declared terrorism within eight minutes.

Speaking in front of her offices at 10 Downing Street, she denounced the assault as an act of “hatred” and “evil” against innocent civilians during the holy month of Ramadan, and said security at mosques would be bolstered.

Calling the attack a “sickening attempt” to destroy freedoms, Mrs May added: “This was an attack on Muslims near their place of worship and like all terrorism, in whatever form, it shares the same fundamental goal: It seeks to drive us apart.”

“There has been far too much tolerance of extremism ... including Islamophobia,” she said, adding that the government would create a new commission to fight extremism in the same way as racism.

The premier has faced criticism for her record on security after the previous series of attacks blamed on Islamist militants. She has also been criticised for her response to a fire in a London tower block last Wednesday which killed at least 79 people.

Mr Harun Khan, secretary-general of the Muslim Council of Britain, said he recognised that many Muslims would be angry about the attack and called for calm, but he also warned of a rising tide of anti-Islamic sentiment.

The chairman of the Finsbury Park Mosque and other faith leaders in London held a moment of silence for the victims.

After the silence, Mr Mohammed Kozbar read a brief statement declaring that “an attack on one faith is an attack on all faiths”.

Residents of London, a multicultural city with a large Muslim population, have predominantly responded with equanimity, solidarity and tolerance towards Muslims following recent attacks perpetrated by extremists.

Just over two weeks ago, three Islamist militants drove into pedestrians on London Bridge and stabbed people at nearby restaurants and bars, killing eight.

The latest incident also follows a suicide bombing at a pop concert in Manchester in May which killed 22.

Yesterday, a sense of unity prevailed among Londoners.

“We want to recognise this as an incident the same as other incidents,” said Ms Deb Hermer, a 20-year resident of Finsbury Park who left a bouquet of flowers at the gate of the mosque. “This is no less important than other incidents.”

But Muslim leaders and human rights advocates have warned that some could try to use the recent terrorist attacks to stir hostility against Muslims, and foster the notion of a culture war between Islam and the West.

According to the office of the mayor of London, in the six days after the terrorist attack at London Bridge and Borough Market on June 3, the Metropolitan Police reported 120 Islamophobic events, compared with 36 the previous week. It added that hate crimes in general had been growing.