(Corrects age to 69 from 68 in first paragraph, deletes repetition in paragraph 5)
By Katharine Houreld
ISLAMABAD, Jan 24 (Reuters) - Pakistan has handed a death sentence for blasphemy to a 69-year-old Briton with a history of mental illness, even though his lawyers were barred from the courtroom partway through the trial, the lawyers said on Friday.
Accusations of blasphemy are surging in Pakistan, according to an Islamabad-based think-tank, the Center for Research and Security Studies. Many analysts see the claims as score-settling or a front for property grabs.
The charges are hard to fight because the law does not define what is blasphemous and presenting the evidence can sometimes itself be considered a fresh infringement.
Blasphemy is punishable by death in Muslim-majority Pakistan.
Muhammad Asghar from Edinburgh was sentenced to death on Thursday, the law firm said, citing court officials in the city of Rawalpindi, neighbouring the capital.
The firm said it was not present during the judgment because the judge had prevented it from representing Asghar in court since October.
He was arrested in 2010 after writing letters to a lawyer and politician claiming to be a prophet. Though Asghar did not post the letters, a disgruntled tenant whom he was in the process of evicting took them to police, the law firm said.
Asghar has previously been detained under the mental health act in Britain and diagnosed with paranoid schizophrenia, it added.
After the removal of the law firm, Asghar was appointed a state counsel, who did not put his medical history in evidence or call witnesses in his defence, and did not question a state-appointed board that declared him sane, the firm said.
The state counsel could not immediately be reached for comment.
The law firm asked not to be identified for fear of being targeted by extremists. Lawyers defending those accused of blasphemy frequently receive death threats and politicians supporting reform of the law have been killed.
A British doctor, 72-year-old Masood Ahmad, is also in prison in Pakistan, charged with blasphemy after a mullah used a mobile telephone to covertly record a conversation with him in his dispensary. (Editing by Clarence Fernandez)