Around 1,100 people have been called up to join the search for six Russian tourists who were reported missing late last month in a canoeing trip on a river in northwest China's Xinjiang, but no clues have been found, local authorities said Sunday.

By Sunday evening, the searchers, including armed police, local farmers and herdsman, had combed a total of 406 kilometers of the middle and lower reaches of the Yurungkax River in southern Xinjiang, an official with Hotan Prefecture told Xinhua late Sunday night.

More than 300 people from Yutian County, located in the upper reaches of the river, have also searched 80 kilometers of the river, the official said.

The six Russians flew to Urumqi, the regional capital of Xinjiang, on August 11 and then flew to Hotan. They later arrived by bus at Pulu Village, Yutian County, where the Yurungkax River originates, according to Zhang Hong, a local Russian-language interpreter for the missing Russians.

According to the original plan, the expedition team would arrive at the banks of the Yurungkax River that flows through Hotan on August 20. They would start canoeing the next day towards Cele and finish at Kashitashi Township in Hotan County, 30 km from Hotan City, where they would meet Zhang.

However, the six Russians failed to show up on September 2 as agreed.

A special eight-member search and rescue team has also left Pulu Village for the starting site of the canoe trip. The estimated arrival time is two days, the Hotan official said.

But as the source of the river is 5,000 to 6,000 meters above sea level with rugged and mountainous roads, the searching would be "extremely difficult", the official added.

Helicopters scheduled to arrive in Hotan on Sunday to join the search and rescue efforts have been delayed due to weather conditions. They will arrive on Monday.

(Xinhua News Agency September 10, 2007)