MOSCOW (AP) — One of the imprisoned members of the Russian punk group Pussy Riot declared a hunger strike on Monday to protest what she described as inhumane working conditions and threats to her life at a women's penal colony.

Nadezhda Tolokonnikova is serving a two-year sentence for "hooliganism motivated by religious hatred." She and two other group members were arrested in early 2012 after Pussy Riot burst into Moscow's main Orthodox cathedral and tried to perform a "punk prayer" denouncing Vladimir Putin.

In a passionate five-page letter published on the group's blog, Tolokonnikova said inmates in her penal colony are forced to work up to 17 hours a day in a shop that makes police uniforms in order to fulfill the quotas. Brigades that fail to meet the quotas are punished by being denied food, prevented from using the bathroom or made to stand outside in the cold, she wrote.

She also said the deputy warden threatened her last month by suggesting that other prisoners would be encouraged to kill her in retribution for her attempts to challenge the prison system.

"If they find out that this happened because of you, then things will certainly never be bad for you because nothing is ever bad in the next world," Tolokonnikova quoted the deputy warden as saying.

She described a system where inmates with ties to the prison administration are used to terrorize other inmates to keep them in line.

Tolokonnikova submitted separate complaints to Russia's chief investigative agency and the prison service about the threats she said she has received and the working conditions at the penal colony in the Mordovia region, about 500 kilometers (300 miles) east of Moscow.

The prison service said the inmates work in two shifts and denied that the women spend any more than eight hours per day in the sewing shop, the Interfax news agency reported.

The head of the presidential human rights council, Mikhail Fedotov, said on Twitter that four members of the council would travel to the prison on Tuesday to look into the complaints.

Tolokonnikova said she first appealed to the prison administration to shorten the work day and call off the inmates threatening her, but it led only to increased pressure.

"Therefore, on Sept. 23, I am declaring a hunger strike and refusing to take part in the slave labor in the colony until the administration starts obeying the law and stops treating incarcerated women like cattle thrown out of the justice system to serve the needs of the sewing industry but like people," she wrote.