At least 1,000 British Muslims protested in central London on Sunday against the “insulting depictions”, as they put it, of the Prophet Mohammed by French newspaper Charlie Hebdo.

According to the Reuters news agency, the protesters gathered near Prime Minister David Cameron’s office in London’s Whitehall government district carrying placards with slogans such as “Stand Up For the Prophet.”

The event comes weeks after 17 people were killed in three days of violence last month in France that began when two Islamist gunmen burst into Charlie Hebdo’s Paris offices, opening fire in revenge for its publication of satirical images of Mohammed.

Sunday’s protest organizers condemned the Paris attacks, but said the magazine should not publish cartoons of the prophet.

Imams delivered speeches and the crowds paused to pray before handing in an online petition to Cameron’s office signed by over 100,000 Muslims.

The petition, organized by a group called Muslim Action Forum, denounced those who had produced cartoons of the prophet, calling them “an affront to the norms of civilized society”, according to Reuters.

A leaflet circulated by the event’s organizers said depictions of Mohammed by Charlie Hebdo and others was “a stark reminder” that freedom of speech was “regularly utilized to insult personalities that others consider sacred”.

The edition of the magazine in question was the first one published after its headquarters were targeted by Islamist terrorists, and showed the Prophet Mohammed with a tear in his eye, under the headline “All is forgiven”.

He holds a sign reading “Je suis Charlie”, the slogan that has become a global rallying cry for those expressing sympathy for the victims and support for freedom of speech.

The magazine’s new issue sold out across France in record time, but the Muslim world was not as sympathetic.

The Afghan Taliban condemned its publication of further Mohammed cartoons and praised the gunmen, saying they were “bringing the perpetrators of the obscene act to justice”.

Angry opponents in countries from Pakistan and Turkey, the Philippines and Mauritania staged protests over the new cartoons.

A Turkish court ordered a block on websites featuring images of the cover, while Senegal said it was banning the dissemination of Charlie Hebdo and the French daily Liberation, which also put a cartoon of the Mohammed on the front page.