The sister of a Chinese journalist who recently disappeared after completing a documentary on labor camp abuses says state security officials have detained the photographer.

Beijing-based photographer Du Bin's sister Du Jirong said Thursday that an officer at the local You'anmen police station verbally informed her that Du Bin was being held at a detention center under state security orders.

Hu Jia, a close friend of the photographer, says Du Bin was last heard from on May 31 and that his apartment was searched by police the next day.

Hu says Du's detention is likely related to his work exposing torture allegedly inflicted on detainees at a notorious labor camp in northeastern China as well as his work gathering accounts of the 1989 military crackdown on pro-democracy protesters in Beijing.