A doctor who was attacked by a patient he had treated more than 20 years ago was still in critical condition after eight hours of treatment on Friday afternoon.

According to the Guangdong General Hospital in Guangzhou, Guangdong province, the hospital is organizing senior experts and doctors to help save Chen Zhongwei, who is in the intensive care unit for further medical observation and treatment after surgery.

"Doctors are doing what they can to help rescue Chen," said a statement from the hospital.

Meanwhile, the hospital said it will actively cooperate with police to investigate the case, in which Chen was stabbed more than 30 times from head to foot on Thursday evening.

The doctor was attacked by a man who followed him home at 5:20 pm. Chen's family immediately sought police help and helped send Chen to hospital after he was stabbed and suffered from massive bleeding.

Chen, 60, former director of the executive department of stomatology of the Guangdong General Hospital, had retired earlier this year.

The suspect committed suicide by jumping off the 18th-floor balcony in Chen's home.

According to a police, the unnamed man was a patient Chen treated 25 years ago. The suspect was reported to have previously sought compensation and made trouble before he attacked Chen, leading Chen to seek police help.

Liao Xinbo, an inspector with the Guangdong Provincial Commission of Health and Family Planning, said he was shocked when he learned Chen was attacked.

"Chen is an honest, low-key and capable doctor," Liao said.

Wu Shaolin, executive vice-president of the Guangdong Provincial Medical Doctor Association, said doctors should be respected by patients and society as more than 60 percent of doctors have to work overtime, or more than 40 hours a week, to serve their patients.

"Those who attack doctors should be seriously punished," Wu told China Daily on Friday.

Wang Hui, deputy director of the Guangdong Mediation Commission of Harmony Doctor and Patient Relations, called for improved medical facilities to make it easier for people to see doctors and ease the high tensions between doctors and patients.

Chen Han contributed to this story.

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