A doctor examines a patient with HIV virus at the Nanqu branch of Zhongshan Second People's Hospital in Zhongshan city, South China's Guangdong province, on Dec 20, 2015. [Photo by Xiao Bing/provided to chinadaily.com.cn]

Under these circumstances, the hospital is different from other hospitals.

As for the inmates admitted to the hospital, doctors and nurses treat them while police stand beside them in case the suspects might harm the medical workers.

The patients at the hospital don't have as much freedom as their counterparts at other hospitals, but they don't need to worry about the medical expenditure as it all taken care of by the government.

And suspects are not sent back to the prison until their physical condition is good enough to live with other inmates, said Wang Jun, head of the hospital.

Once as many as 148 drug addicts were sent to the hospital in a single batch, a so big number that the hospital had to arrange 68 extra beds as it had only 80.