SHANGHAI - Rescue teams searched Monday for dozens of people, some of them schoolchildren, missing after a packed bus slid off a ferry into a river in southeastern China, state media reported.

There was no immediate word on the cause of the accident. Up to 30 passengers were aboard the bus in a semi-rural area of Jiangxi province, the Xinhua News Agency said.

Six people were pulled from the river after the accident, five of whom survived, the report said. Search efforts were ongoing, it said. Reports said the body recovered was that of an elderly woman and others missing included a number children headed to summer school classes.

The accident which struck at about 11:00 a.m. (0300 GMT) on the Xinjiang River in Jiangxi's Yugan county, a region of lakes and rivers about 700 kilometers (435 miles) southeast of Shanghai.

Eight hours later, there was no word on the fate of those missing. Calls to county government offices either rang unanswered or were answered by people who said they had no knowledge of the accident.

Such accidents remain common in rural China, despite repeated attempts to boost safety. Southeastern China has also entered its annual flood season, although it wasn't clear whether high water or stormy weather played a part in the accident.

In a separate report, Xinhua said a bus plunged off a mountain road in Guizhou province southwest of Jiangxi on Sunday, killing 12 people and injuring eight others.

The bus was carrying 20 people deep in the hills of Guizhou province when it crashed through a guardrail and into a 10-meter (33-foot) deep culvert on Sunday afternoon, the report said.

It said 11 people died at the scene and another died in a hospital.

The cause of the crash wasn't given and Xinhua said the driver remained in a coma. Such accidents are often blamed on poorly maintained over overloaded vehicles, along with speeding and exhausted and inattentive drivers.