Rescuers recovered two more bodies Wednesday morning, bringing the death toll to 15 after a bus plunged into a river in northeast China's Heilongjiang Province in May.

Rescuers are continuing to search for four others still missing.

The two bodies have been identified as Cheng Liru, a 6-year-old girl, and Yang Yuxian, a 63-year-old man. They were villagers from Qinlao Township and Jiusheng Township of Qing'an County, according to the rescue headquarters.

A bus carrying 22 people plunged into the Hulan River in Qing'an County at 3:00 p.m. on May 23 as it was being driven on to a ferry. Only three people in the bus, including the driver, were rescued unharmed.

Operators of the illegal ferry service were blamed for the accident. Ferry staff failed to unload all the bus passengers before the vehicle went onboard, breaking transport regulations.

Gu Chunfeng, the operator, has been detained for allegedly operating the illegal ferry service.