LONDON — Despite calls by British politicians and religious leaders for calm, there has been a rise in threats and invective against Muslims across the country in the wake of the killing of an off-duty soldier on a London street by two men who shouted Islamic invocations.
The police and Muslim community groups have said that anti-Muslim episodes have occurred in many parts of the country, with the most common involving the posting of derogatory — and, the police said, in some cases inflammatory — messages on social media sites like Twitter.
A number of arrests have been made, with criminal charges being leveled in some cases under laws against inciting racial or religious hatred, and Muslim community leaders have reported rising concern among the estimated 2.5 million Muslims in Britain.
Fiyaz Mughal, director of Faith Matters, a group that seeks to promote harmony among religious groups, said in a BBC interview on Saturday that the anti-Muslim episodes had included graffiti being scrawled on the walls and windows of mosques and Muslim-owned businesses, women’s head scarves being yanked off and verbal abuse. He described the occurrences as “quite aggressive.”
The brutality of the assault, which took place Wednesday in Woolwich, has stirred a wave of public outrage. The soldier, Lee Rigby, was a 25-year-old army bandsman and machine-gunner.
The two men who carried out the killing were shot and wounded by the police. One of the two men was captured on video hectoring a gathering crowd, gesturing with his bloodied hands while still grasping two heavy cleavers. The man, later identified as Michael Adebolajo, 28, justified the attack as revenge for British military deployments in Muslim countries, including the stationing of 10,000 troops in Afghanistan.
In the aftermath of the assault, which the police have characterized as a terrorist attack, there have been appeals from many of Britain’s political and religious leaders for a renewed commitment to tolerance among religious and ethnic groups.
One of the first to speak was Prime Minister David Cameron, who cut short a European tour to return to London. “We have all seen images that are deeply shocking,” he said. “The people who did this were trying to divide us. They should know: something like this will only bring us together and make us stronger.”
That was followed by similar messages from faith leaders, including the archbishop of Canterbury, the Most Rev. Justin Welby, who visited a community in Birmingham with Ibrahim Mogra, a leader of the Muslim Council of Britain and declared, “This is very much a time for communities to come together.” Mr. Mogra, echoing other Muslim representatives in Britain, called the soldier’s killing “a betrayal of Islam” and “a truly barbarous act” with no basis in Islam.
On Friday night, a man claiming to be a friend of Mr. Adebolajo’s, Abu Nusaybah,appeared on a BBC television program saying Mr. Adebolajo had been “a changed man” since he returned last year from a trip to Kenya. The trip appeared to have been the one cited by British security officials who said that Mr. Adebolajo had planned at one stage to join the Shabab, an Islamist insurgent group in Somalia.
The police arrested Mr. Nusaybah after the interview, while he was still at the BBC. They said he was wanted on suspicion of involvement in unspecified acts of terrorism unrelated to the soldier’s killing.