By Michael Bristow
BBC News, Beijing

China has launched a three-month campaign to "eliminate unnatural deaths" of prison inmates.

The campaign comes after the deaths of at least five prisoners in police custody in recent months.

The UN's Committee Against Torture recently said there was evidence that ill-treatment of Chinese prisoners was both routine and widespread.

With this new campaign, China seems to be acknowledging that its inmates are not always treated as they should be.

'Nightmare' death

It was the death of 24-year-old Li Qiaoming in February that brought this issue to public attention.

He was beaten to death by three fellow prisoners while in detention in Jinning County in southern China's Yunnan Province, according to the state-run Xinhua news agency.

Prison officers initially claimed he died while playing a game of hide-and-seek with other inmates.

There have been at least four other suspicious deaths of prisoners in recent months.

One man, 50-year-old Li Wenyan, allegedly died while in the middle of a "nightmare", Xinhua quoted a senior prison official as saying.

Prison deaths are a sensitive subject, but these have been widely reported in the Chinese media and on the internet.

Last month the English-language China Daily ran a full-page article on the subject, saying experts were calling for inmates to be put into "neutral hands".

The new three-month campaign, launched by China's Ministry of Public Security, aims to improve prison officers' respect for the law, professional ethics and human rights.

"Officials should be brave to reveal their problems in the management of prisons and detention centres, and should exert efforts to address them," the ministry said.

China has often faced criticism about its treatment of prisoners.

The UN's Committee Against Torture said last November that it remained "deeply concerned about the continued allegations... of routine and widespread use of torture and ill-treatment of suspects in police custody".