Last month, after being offended by a tweet, Tanweer Ahmed traveled 200 miles in an Uber car from Bradford, in England, to Glasgow, in Scotland. The seemingly innocuous, even heartfelt tweet was written by Asad Shah, and wished his adopted countrymen a happy Easter.

Upcoming special event ;- GOOD FRIDAY AND VERY HAPPY EASTER ESPECIALLY TO MY BELOVED CHRISTIAN NATION X !...

Posted by Asad Shah on Thursday, March 24, 2016

Ahmed waited for 40-year-old Shah to leave the convenience store in Glasgow where he worked, then stabbed him 30 times, stamped on his head, and sat on his chest while Shah lay unconscious, authorities allege. Shah died of his wounds later that night.

The hatred that Ahmed, 32, apparently felt for Shah wasn't because of his kind words about Christians, but because Shah was a member of the small and long-persecuted sect of Muslims called the Ahmadiyya.

This week, leaflets have been found in universities, mosques and shopping centers across London advocating that each Ahmadiyya be given three days to "get back into the Islamic fold. If he does not, he will be awarded capital punishment."

The leaflets refer to Ahmadiyyas as "Qadianis," which is considered pejorative by the Ahmadiyya, who are also known as Ahmadis or Ahmedis. The term is a reference to the town of Qadian, in India's state of Punjab, where Mirza Ghulam Ahmad was born. Ahmad, who lived in pre-Partition India at the turn of the 20th century, claimed that he was the foretold Mahdi, or Messiah, but most Muslims believe Muhammad to be the final prophet. For these beliefs, Ahmad's followers have been shunned, particularly in Pakistan, where their numbers are highest. The Pakistani state forbids them by law from claiming to be Muslim. Hundreds have been murdered or killed in terrorist attacks there in the past few years alone.

Leaflets like these have been distributed before, according to leaders of Britain's Ahmadiyya community, but after Shah's slaying, they have added to a growing sense of unease in a country many have found to be an asylum. This new iteration, obtained by IBTimes UK, says Ahmadiyyas are "worse than apostates" because they present themselves as Muslims. The leaflets were made by an organization called Khatm-e-Nubuwwat, which means "Finality of Prophethood" in Arabic.

In a recent column reacting to Shah's killing, British anti-extremism activist Maajid Nawaz writes that intolerance of the Ahmadiyya is on the rise there, and much of it tied to anti-blasphemy fervor in Pakistan. Massive protests recently roiled Pakistan's capital, calling for, among other demands, the immediate execution of anyone proved to be blaspheming, which would include all Ahmadiyya. Imams of some of Britain's largest mosques have spoken in favor of the protests.

In an example provided by Nawaz, the Ahmadiyya community took out a two-page ad in the British newspaper Luton on Sunday to celebrate the 125th anniversary of their existence, but the paper was so overwhelmed by complaints from the majority Sunni Muslim community that it had to issue this mealy-mouthed response, which Nawaz tweeted:

In a deposition given by Tanweer Ahmed this week, he admitted to killing Asad Shah, employing much of the same rhetoric as the leaflets. Saying Shah "disrespected" Islam and "claimed to be a prophet," he went on to assure the court that the attack had "nothing at all to do with Christianity or any religious beliefs." Police have charged him with "religiously prejudiced" murder.

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