Authorities at Yangon’s Insein Prison have refused to allow medical treatment to nearly 90 detainees who were brutally beaten a week ago during a nationwide “Silent Strike” protest against Myanmar's military junta rule, the detainees’ relatives and lawyers said Friday.

Dozens of political prisoners showed their solidarity with nationwide demonstrations by staying in their cells after morning roll call and singing the protest song “Our Pledge in Blood” in unison.

Authorities at the infamous Yangon detention facility attacked the prisoners for joining the Silent Strike, which was held on Human Rights Day on Dec. 10. The strike left many cities and towns empty as citizens stayed home in protest of the military regime and its brutal crackdown following its Feb. 1 coup.

At Insein, prison authorities threw strike organizers into solitary confinement and shackled their legs, sources close to the prisoners told RFA in an earlier report.

Some of the prisoners were critically wounded but were denied medical care, while some female prisoners were subjected to sexual harassment, sources said.

A pro-democracy student leader who had joined the prison strike suffered critical head and back injuries that were left untreated. He was instead placed in solitary confinement as punishment for participating, his family said.

Sitt Naing, vice chairman of the Yangon University of Education Students’ Union, who was involved in the Silent Strike in Insein Prison, is in critical condition, a relative said.

“As family members, we are worried about his life,” said the woman, who declined to give her name out of fear of retribution. “It is because he is not even allowed to apply medicine to the wounds, let alone receive medical treatment.

“We believe that his life is still in danger,” she added. “He urgently needs medical treatment.”

Wai Yan Phyo Moe, vice chairman of the All Burma Federation of Student Unions, and Lay Pyay Soe Moe, spokesman for student rights for the Yangon University Students’ Union, were also severely beaten during the crackdown, family members said. They are reportedly being held in solitary confinement with their legs in shackles.

Mya Moe, mother of Lay Pyay Soe Moe, told RFA that prison staff denied her son medical help. “On the day of the trial, the lawyers brought some ointment for his wounds but were not allowed to apply them,” she said. “He was rudely told to put his shirt back on and to ‘stop the nonsense.’ That’s how the prison staff talked to him.”

RFA could not reach Insein Prison officials or Myanmar’s Ministry of Justice. Ministries have not responded to media requests for comment since the coup, and only junta spokesmen can issue statements.

A spokesman for the Assistance Association of Political Prisoners (AAPP), a nonprofit human rights organization based in Mae Sot, Thailand, said refusing medical treatment to wounded detainees was a “grave violation of human rights” by prison authorities and that those responsible should be held accountable.

The spokesman asked not to be identified for safety reasons.

A lawyer representing some of the prisoners said the victims asked the court for their injuries to be recorded, but the court refused.

“We saw some clients at trial who had been beaten,” he said. “When they were brought in, the lawyers showed the injuries they had sustained and requested that the court put them on record, but some courts rejected the requests.”

Junta spokesman Maj. Gen. Zaw Min Tun in an earlier report denied that there had been any protests inside Insein Prison.

Following the Silent Strike, prison authorities enacted stricter measures for detainees, transferring some to cells with criminals and other forms of repression that violated human rights, said Tun Kyi, a member of the Former Political Prisoners Society.

“A prison is one of the worst and most serious mechanisms for violating human rights, and it’s where human dignity can be taken away,” he said.

Before being taken out of Insein Prison for court hearings, authorities instructed female prisoners to take off their sarongs so they could feel and search their genitals, he said.

“It was OK for inmates to send letters to their families in the past, and families could also send in letters, but now they have banned all these exchanges,” he said.

News of the prisoner maltreatment has been leaked from the inside by detainees clandestinely passing small notes to family members and their lawyers during their trials.

When prisoners are taken to court for hearings, authorities constantly monitor their conversations with their attorneys and have threatened the lawyers not to leak information to the media, attorneys and family members of those imprisoned said.

The International Committee of the Red Cross, which used to make humanitarian visits to prisons until March 2020, is still waiting for permission to resume its prison activities.

On Friday, the AAPP reported that junta forces have killed 1,346 people and arrested 11,023 others since the Feb. 1 coup.