A Pakistani lawyer who has successfully overturned a number of convictions for "blasphemy" has said he believes his life is in danger from extremists.
Saif ul Malook most recently oversaw the acquittal of a Christian couple who had been sentenced to death.
Mr Malook shared social media posts with the BBC which called for him to be "executed" for securing the acquittal.
Blasphemy is a deeply emotive topic in Muslim-majority Pakistan and is legally punishable by death.
While no one has ever been executed for the offence, dozens of people accused of blaspheming have been killed by vigilantes.
Human rights groups say the country's blasphemy laws often unfairly target religious minorities and can be used in personal feuds.
Earlier this month, the high court in Lahore quashed the convictions of Christian couple Shagufta Kausar and her husband Shafqat Emmanuel, citing a lack of evidence.
The pair were sentenced to death in 2014 for allegedly sending blasphemous text messages insulting the Prophet Muhammad. They insisted they were innocent. Ms Kausar's brother told the BBC last year he doubted the couple were literate enough even to have written the messages.
The couple's lawyer, Mr Malook, previously also represented Asia Bibi, a Christian villager who spent eight years on death row in a case that attracted international condemnation.
Ms Bibi was eventually acquitted by Pakistan's supreme court in 2018 and subsequently flown out of the country. The legal ruling led to large and violent protests by thousands of followers of a hardline cleric.
But Mr Malook, who is the most prominent lawyer defending blasphemy cases in Pakistan, told the BBC that he considered the current threats against him the "most dangerous" he had ever received.
"Even this was not done during Asia Bibi's case," he said. "Now they [the extremists] think I am the only hurdle in their way."
He criticised the government for not providing him with adequate security. "Not even a clerk from the Pakistani government has contacted me," he said. Pakistani officials did not reply to a request for comment.
It is not clear how serious the specific threats are to Mr Malook, but in 2014 a lawyer representing another blasphemy defendant was shot dead. Rashid Rehman was sitting in his office when he was shot and two of his assistants were injured.
Blasphemy convictions in Pakistan by lower courts are often overturned on appeal. Human rights activists say more junior judges are intimidated into convicting suspects despite flaws in their cases.
Hearings at Lahore High Court in the case of Ms Kausar, a caretaker at a Christian school, and her paralysed husband Mr Emmanuel, had been repeatedly delayed.
Mr Malook suggested the judges were concerned at the possibility of being targeted themselves if they acquitted the pair. In April, however, the European Parliament passed a resolution urging Pakistan to reform its blasphemy laws, citing concerns over the Kausar-Emmanuel case in particular.
Mr Malook told the BBC that had case had not been highlighted internationally, he feared the appeal would've been delayed indefinitely.