BEIJING (AFP) - A senior Chinese official killed himself in his Beijing office this week, reports said Thursday, in the latest mysterious suicide of a ruling Communist Party cadre.

Mr Xu Ye'an was deputy chief of China's State Bureau for Letters and Calls, the agency that fields grievances from citizens over injustices or disputes such as illegal land grabs or police misconduct. The 58-year-old had been deputy chief of the bureau since 2011.

According to the respected magazine Caixin, Mr Xu was discovered to have killed himself in his office on Tuesday morning, although the details surrounding his death remain unclear.

"It is learnt that Xu is not in good health lately and was suffering from tinnitus over the past few months," Caixin reported, citing a person close to the Bureau for Letters and Calls. "He was always in a bad mood, although the exact reason is not clear."

Under a system dating from imperial times, Chinese people can "petition" government authorities at various levels.

Millions do so each year, but many complain of official indifference to their concerns and those from the provinces will sometimes travel to Beijing to lodge their grievances with the national authorities.

Local officials often work to prevent complaints being lodged against them in the capital to preserve their area's image and their own career prospects.

Mr Xu's death comes after the Communist Party mouthpiece the People's Daily reported on its English-language Twitter feed that Mr Li Wufeng, deputy director of China's government information department, "fell to death".

"Cause is unknown," it added, without elaborating.

Caixin also reported on Mr Li's death, although a posting on its website was soon deleted.

Last week, Mr Zhou Yu, a senior police official in the mega-city of Chongqing, apparently committed suicide.

Mr Zhou, a key figure in disgraced Chongqing party chief Bo Xilai's crackdown on organised crime, was found hanging in a hotel room, according to local police.

A police investigation found that Mr Zhou had been depressed due to poor health, and his body was cremated on Monday, reports said.