The women in the United Kingdom were told to stay indoors yesterday amid fears of suspected vandalism against Muslim communities on the ‘Punish a Muslim Day.' As the viral anti-Muslim violence campaign that originated in the U.K. spreads, security was tightened at New York mosques and Islamic centers in the United States.

A letter calling on people to perpetrate violent crimes against Britain's Muslim community which has been circulating since last month, advertises April 3 as a day of violence against the U.K.'s Muslim minority.The letter calls on people to attack Muslims in the form of verbal abuse or physical assault, such as by removing a woman's hijab or headscarf, or by throwing acid on them. The counter-terrorism police said it had received reports of "potentially malicious communications sent to individuals across the U.K.."

The letter shows a scale of "points" based on the action taken against Muslims. "There will be rewards based on action taken," the letter says.

The hate letter urges terrorist acts such as to "butcher a Muslim using gun, knife, vehicle or otherwise," and "burn or bomb a mosque," with "Nuke Mecca" being the top hate crime listed, offering 2,500 "points."

A Muslim Bradford resident who also received the letter, Councillor Riaz Ahmed, commented that the disturbing content intends to stir up racial violence. He also said that he is particularly concerned about the letter's mention of Muslim-on-Muslim acid attacks due to their increased use in recent years, especially in London. "I am alarmed by its content, especially where it mentions acid because of all the recent reports in the media of acid attacks."Tell MAMA, a group tracking anti-Muslim hate crime in the U.K., said the letter "has caused quite a lot of fear within the community," as reported by Anadolu Agency (AA).

Also in March, four high-profile Muslim MPs received suspicious packages that contained a noxious substance, according to police. One staff member was also hospitalized after coming into contact with the substance and the MPs' offices were later cordoned off by police.

According to statistics provided by the British Home Office, hate crimes spiked not only after the EU referendum result but also after the Westminster Bridge attack, the Manchester Arena attack and the London Bridge attack, which taken together left dozens dead and many more injured.In 2016, some 4,400 religious hate crimes were carried out, a number that went up to 5,949 in 2017. The peculiar nature of the letter itself suggests that it is not in fact genuine and could spawn an organized Internet campaign to stir up emotion within the populations of not only Britain but also the rest of the West.