A Korean human rights activist will undergo a medical checkup this week, a spokesman for a group supporting him said Sunday, amid reports the activist may try to present a medical report to support his claims that he was severely tortured during his detention in China.

Kim Young-hwan has claimed that he was tortured by Chinese security agents, including beatings, electric shocks and sleep deprivation, while under detention in northeastern China for allegedly helping North Korean defectors in China and promoting human rights in North Korea.

The 49-year-old activist was sent back to Seoul last month after being put behind bars in China in March.

"Kim will have a medical checkup at a hospital in Jeonju on the 8th (of August)," said Choi Hong-jae of the group that played a role in Kim's release.

Choi fell short of saying the checkup aims to secure any proof of torture.

Kim has said he wants to have a medical checkup to find proof of torture, although most of the bruises and scars from beatings and electric shocks have disappeared by now.

The former proponent of North Korea's "juche" or self-reliance ideology, who later converted to serve as a fierce critic of the North's human rights violations, has said he was tortured during only the early days of his detention in an apparent effort by Chinese security officials not to leave physical evidence of torture.

Faced with the Chinese government officially denying the alleged torture, the Seoul government wants to have material evidence for the alleged torture before taking the issue to international bodies or any Chinese court.

Kim is to give a press conference to foreign journalists in Seoul on Monday. (Yonhap)