LONDON • London may be the most diverse and tolerant city in the world and is home to more than one million Muslims from dozens of countries. Its mayor, Mr Sadiq Khan, is Muslim and enjoys broad support outside the Muslim community too. When Britain voted to leave the European Union, London voted to stay.
But this proudly cosmopolitan city is now confronted with the tensions and ugliness that have been simmering on the fringes for years and are boiling to the surface.
Like many of London's Muslims, law student Mohammed Abdullah grew tired of defending himself, and his religion, after the recent terrorist attacks.
"It feels like you are under siege," said the 23-year-old, standing outside Finsbury Park Mosque, where earlier a white British man rammed a rental van into a group of worshippers. "I wonder," he said, "is anyone going to write about a 'white Christian terrorist' this time round?"
As Mr Hamdan Omar, also a student, put it: "There are people on both sides who want the clash of civilisations."
Police identified the suspect as Darren Osborne, 47, who lives in Cardiff, Wales.
Prime Minister Theresa May, who has been criticised for her response to the Grenfell Tower fire, denounced the assault as an act of "evil" and "hatred", and promised to bolster security at mosques.
The authorities said they were treating the attack as an act of terrorism against Muslims, while many of the city's Muslim leaders pleaded for calm and warned against a rising tide of anti-Islamic sentiment.
"During the night, ordinary British citizens were set upon while they were going about their lives, completing their night worship," said Mr Harun Khan, the secretary-general of the Muslim Council of Britain. "Over the past weeks and months, Muslims have endured many incidents of Islamophobia, and this is the most violent manifestation to date."
In the week after the June 3 terrorist attack on London Bridge and at Borough Market that killed eight people and was carried out by three men inspired by the Islamic State in Iraq and Syria, police reported 120 Islamophobic events, compared with 36 the previous week.
Throughout Monday in Finsbury Park, one of London's many diverse neighbourhoods, residents left flowers and messages of solidarity outside the mosque.
"With love, sympathy and support to our Muslim neighbours, victims of this horrific act of terrorism," read one handwritten note. "This does not represent Finsbury Park," read another.
There was a sense of relief, carefully expressed, that the suspect was not from the city. "Somehow, it would have been even worse if he had been from our city," said mother of two Zahra Mounia, 45.
But some worried that London's famed tolerance was fraying on the edges. Several residents said they experienced small but unsettling episodes of hostility.
"In London, people feel they must tolerate you, so they won't say anything, but you get the dirty looks," said Ms Suzanne Stone, 42, a convert to Islam who writes children's books. "My friend outside of London gets real abuse."
Many people pointed to the fact that it was Muslims, awake because of Ramadan, who saved a lot of lives in Grenfell Tower by waking up neighbours and alerting the fire department. And it was an imam of the Muslim Welfare House who helped form a protective ring around the van driver on Monday before the police arrested him.
"How many people know that?" asked Mr Omar Hussain, a community worker.