HARBIN -?Twenty-six of the 28 Russian tourists returned home Saturday from northeast China's Heilongjiang Province after their tour bus grazed two dump trucks and overturned, border police said Saturday.

One of the tourists remains hospitalized and is accompanied by another tourist, said an officer of the provincial frontier police.

The accident happened around 5 am Friday on National Highway 202 in the city of Wudalianchi, leaving 17 of the 28 passengers injured.

Two had minor injuries and five suffered skin bruises, doctors said.

An initial investigation showed that morning rainfall might have reduced visibility and caused the driver not seeing the dump trucks, police said.

A further investigation is underway.