An investigation in east China is underway regarding claims that petitioners were thrown into mental institutions.

It was launched Tuesday by the municipal government of Taian City in Shandong Province after a report in the Beijing News on Monday.

The article said several people were instituted over the past two years for "disturbing the social order" in Xintai City, which is under the jurisdiction of Taian.

An official said an investigation team, consisting of 11 local members, was formed. It includes people from the commission of discipline inspection, letters and visits office, public health bureau and the politics and law committee.

The team said it has already confirmed that the five petitioners in the report, who had appealed to higher authorities to have their problems resolved, all had mental illnesses proven by provincial psychiatric institutions.

The five people include Sun Fawu, Shi Hengsheng, Xu Xueling, Li Pingrong and Li Yuanliang.

Further investigation as to whether they had been forcibly admitted is underway.

Shi Hengsheng, an 84-year-old retiree, traveled to Beijing several times to appeal disputes with his neighbors. He was stopped by local officials at the Taian train station and sent to the mental hospital on June 14, 2006. He is still in the hospital.

Sun Fawu, who had gone home, was sent to the mental hospital twice, in July of 2007 and October of this year. He spent about four months in the hospital.

The 57-year-old man from Dagouqiao Village, Quangou County, appealed several times for damages to his house caused by a nearby coal mine.

Xu Xueling, also from Dagouqiao Village, has tried appealing for punishment of the security guards of a local mine who beat her younger sister. She was sent to the hospital in May and sent home after doctors found a tumor in her head.

Three of the patients who are currently in the Xintai Mental Hospital have been involved in petitions, the investigation team said. The hospital institutionalized 242 patients in 2008.