The first of the two China's Miniature Neutron Source Reactors (MNSR) started operations with LEU fuel. The reactor, known as MNSR IAE, is operated by the China Institute of Atomic Energy in Beijing. It first reached criticality in 1984. The conversion was a result of a cooperative project between China Atomic Energy Authority (CAEA) and U.S. Department of Energy.
China has another reactor of this type, MNSR SZ, at the Shenzhen University, Guangdong. The MNSR IAE conversion brings the number of HEU research facilities in China to three - MNSR SZ, ZPR FAST critical assembly, and CEFR experimental fast reactor.
UPDATE: According to an IAE representative, HEU fuel was unloaded in September 2015. The new LEU fuel (12.5% U-235) was loaded in the core on March 3-26, 2016. The reactor reached full power on March 26, 2016.