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, Xinhua quoted local authorities as saying today. By Sunday evening, the searchers, including armed police, local farmers and herdsman, have 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, in the upper reaches of the river, have also searched 80 kilometers of the river, the official said. Meanwhile, the helicopters which were scheduled to arrive in Hotan on Sunday to join the search were delayed due to weather conditions and would arrive Monday.