Six foreign inmates at the Shanghai Qingpu Prison sat the Chinese Proficiency Test (HSK) over the weekend, including three who passed the elementary and intermediate level exam five months ago.

The three-hour exams - split into three levels, elementary, intermediate and advanced - were supervised by prison officers and staff members from the Chinese Proficiency Test Center. The six inmates hail from South Korea, Malaysia, Singapore and Australia.

As the only prison in the city holding foreign inmates, Qingpu Prison emphasizes Chinese culture to help overseas convicts reform, according to prison official Xiao Limin.

"The success in passing the test by six foreign inmates last year was a great encouragement to other convicts, who were also inspired to study Chinese in prison," he said.

A South Korean convict, serving life for manslaughter, is expected to become the first foreign inmate to earn an advanced HSK certificate. The man identified as Kim passed the elementary and intermediate exams last December.