MOSCOW: One of the jailed members of the Pussy Riot punk band, Nadezhda Tolokonnikova, has been hospitalised with headaches and fatigue, the Russian prisons service and her supporters said on Friday.

Tolokonnikova “was transferred to hospital for a diagnostic examination based on her own and her lawyer's wishes,” the spokeswoman told AFP.

The 23-year-old activist has been suffering from headaches for at least a year, said her lawyer, while a fellow band member added Tolokonnikova had complained of overwork in her labour camp.

She is serving a two-year sentence at a prison camp in the Mordovia region in central Russia for staging an anti-Vladimir Putin performance last year in the country's top church.

One other Pussy Riot member, Maria Alyokhina, is serving her two-year term in the Perm region in the Urals. The third jailed band member Yekaterina Samutsevich was freed on appeal.

The spokeswoman for the Federal Service for the Execution of Punishment (FSIN) denied that Tolokonnikova was ill but could not reveal a diagnosis on grounds of medical secrecy.

“Back in spring 2012 while in detention Nadezhda Tolokonnikova repeatedly complained of headaches,” her lawyer Irina Khrunova said in a statement.

“In prison conditions her headaches have intensified.”She added that Tolokonnikova, an attractive doe-eyed brunette and the most recognizable member of the group, had to undergo a barrage of tests before she could be diagnosed and treated.

Samutsevich had first raised the alarm about Tolokonnikova's health in a late-night interview Thursday with opposition Dozhd (Rain) television, revealing that she had been unwell for some time.

“She has complained about her health for a long time,” Samutsevich said.

“A decision was made to take her to a neighbouring prison colony where there is a hospital. She has been there several days,” she added.

She described the prison camp where Tolokonnikova is being held as notorious for its conditions and speculated this may have had an effect on her bandmate.

“Every day she gets up at five and goes to work. She has two shifts. The problem is that they do not let her rest after that and give her other tasks,”said Samutsevich.

“It means she is working all the time and is complaining of being very tired.”In an interview with opposition newspaper Novaya Gazeta last month, Tolokonnikova said she was sewing jackets in her prison's workshop.

The prisoners work in teams and Tolokonnikova contanstantly hurts her fingers keeping up with the rigorous pace at the workshop, she said.

The Pussy Riot's legal team has been trying to get Tolokonnikova freed on the grounds that she has a small child and could have her sentences postponed until her child is older.

The Interfax news agency cited chairman of a Kremlin-linked prisoners' rights watchdog for Mordovia, Gennady Morozov, as suggesting that Tolokonnikova may be in hospital to collect the documents necessary to get her sentence postponed.

He was not immediately available for futher comment.

Speaking to AFP, Tolokonnikova's lawyer Khrunova said: “This is not related to the deferral.”The concerns about Tolokonnikova's health flared on the same day a court in the Perm region was to hear a complaint by Alyokhina against reprimands she has received over her behaviour in prison.

The art group Voina (War) which is affiliated with Pussy Riot said on Twitter later in the day the hearing was postponed until Monday due to problems with video feed.

Pussy Riot's performance in the Christ the Saviour Cathedral outraged the church and shocked many in Russia. But their imprisonment divided society and for the opposition and the West became one of the symbols of repression under President Vladimir Putin.