Jailed monk Ashin Gambira, who was handed a 63-year sentence for his pivotal role in the September 2007 uprising, is in declining health following regular bouts of torture over the past two months at the hands of prison guards.

A letter was sent by the Hong Kong-based Asian Human Rights Commission (AHRC) to President Thein Sein on Tuesday containing “an urgent humanitarian request” that he intervene to stop the treatment of the 32-year-old, who is being held in Kalay prison following a transfer from Khamti prison shortly after his sentencing in November 2008.

The group said it had “received information that he [Gambira] had been assaulted during a prison transfer and that he had been assaulted repeatedly at the [Khamti] Prison over the course of about a month, due to which he has been suffering from head and back injuries.”

It continued that fellow inmates had told of the monk “suffering from fits, in which he frequently cries out in pain and clutches at his head.

“The prison authorities then have to hold him down to administer a drug via injection, perhaps a sedative, after which he goes quiet and falls unconscious. When he comes out of unconsciousness, he slurs his speech.”

Min Lwin Oo, a Burmese lawyer at the AHRC, told DVB that abuse at the hands of prison guards had occurred “on daily basis for almost a month”. AHRC described his physical and mental health as “very precarious”.

Since his detention, authorities have had a hard time silencing Gambira, who formed the All Burma Monks’ Association shortly before the 2007 protests erupted. In May this year he was among four Kalay inmates who went on hunger strike after the government apparently ignored a letter in which they complained they were being denied adequate healthcare, food and the freedom to communicate with their families.

It coincided with a hunger strike in Rangoon’s infamous Insein prison resulting from a controversial amnesty in which political prisoners comprised only 55 of the nearly 15,000 inmates released.

Ashin Gambira is no stranger to brutal treatment from Burmese authorities: previous demands he made for former junta chief Than Shwe to visit him in jail and begin dialogue were quickly dealt with by wardens, who filled his mouth with a cloth, taped him up and repeatedly beat him.

It is not clear what the motives behind his current treatment are.

An activist released from prison during another amnesty earlier this month has said he will file a complaint with the government-backed National Human Rights Commission detailing abuse at the hands of prison authorities in Irrawaddy division’s Myaungmya jail.