ISLAMABAD: Extremist threats have hampered the murder trial of Pakistan's former minority affairs minister Shahbaz Bhatti, who was gunned down in Islamabad in March 2011, the All Pakistan Minorities Alliance (APMA) said Saturday.

Shahbaz Bhatti, a Catholic, had been a vocal opponent of Pakistan's controversial blasphemy law.

Blasphemy is an extremely sensitive issue in a country where 97 per cent of the population is Muslim and can carry the death penalty.

“Threatening pamphlets claiming to be from the Punjabi Taliban were found in the office of our key witness, whose name cannot be disclosed for security,” Shamoon Gill, spokesman of APMA, told AFP.

He said the pamphlets had warned the witness to “stay away from the case or get ready to be eliminated along with his family.” “He is terrified, he continues changing his place and faces serious life threats,” Gill said.

The witness is supposed to appear before an anti-terrorism court on February 19.

Paul Bhatti, brother of the former minority minister who had also served as a federal minority minister after his brother was gunned down, is the complainant in the case.

He is currently in Italy after facing warnings from extremists that he too would be murdered.

His lawyer Rana Abdul Hameed said his absence from the country has affected progress of the case.

Hameed said he too had received death threats but would stand up to extremists and bring the trial to its logical conclusion.

“I constantly receive death threats but I have pledged myself to pursue the case,” he said.

Hameed also represented Rimsha Masih, a Christian girl who fled to Canada with her family last year after the charges were dropped.

“Pamphlets are dropped in my office warning me to disassociate myself from the case” he said.

“They say you freed Rimsha, now you are trying to convict our comrades, you should be taught a lesson,” he added.

“Paul Bhatti is abroad, he cannot come to Pakistan, our witness has been threatened, we are receiving constant threats, what can you then expect from the case, it won't go anywhere,” he added.

Pakistan's tough blasphemy laws have attracted criticism from rights groups, who say they are frequently abused to settle personal scores.

Last month, a 69-year-old British-Pakistani with dual nationality was sentenced to death for blasphemy.

In 2011, Punjab governor Salmaan Taseer was assassinated for demanding that the blasphemy law be reformed.

Asia Bibi, a Christian mother of five, remains in prison after being sentenced to death in November 2010 in a blasphemy case.