HOHHOT, March 20 (Xinhua) -- Flood water is pouring into a town in north China's Inner Mongolia Autonomous Region after sections of the main embankment of China's second longest river -- the Yellow River -- collapsed, local authorities said on Thursday afternoon.

    About 13,000 people in six villages on the southern bank were evacuated from their homes to the Kubuqi desert, around 10 kilometers from the town, on Wednesday night.

    The few remaining people, including the rescuers, were moving out as the water moved into the town at about 5 p.m., a Xinhua reporter on the scene has learned. No casualties have been reported.

    Some 600 middle and primary school students in the town were evacuated to four schools in Xini town where the Hangqi Banner government is located.

    Around 700 tents as well as drinking water and food have been sent to the temporary residential area. Seven ambulances and 30 doctors are nearby, according to the flood control headquarters in Hangji on Thursday afternoon.

    The water approached Duguitala town, Hangji Banner in Ordos City at 4:10 p.m., where a 30-meter section of the embankment collapsed on Thursday morning. A 450-meter stretch lower down burst on Wednesday afternoon, said Niu Shaoyun, deputy director of the flood control headquarters in Hangji.

    The dike had been soaked with water for a long time with only 50 centimeters between the water level and the dyke top, which led to the collapses, said Niu.

    The vulnerable embankment in the area was another cause of the collapses, Niu added. Of the 231.6-km embankment in Hangji Banner,90 km failed to meet the required standard.

    "We estimate that 40 kilometers of the main embankments are in danger of further erosion as the river level continues to rise by nearly five centimeters an hour in some sections," said Niu.

    The icy waters were flowing through the breaches at 1,450 cubicmeters per second on Thursday and other sections of the embankment were holding water at dangerous levels, said Niu.

    Flood control authorities planned to channel the water through roadside trenches to a dry river bed 17 km from the collapsed bank, he said.

    The river's ice flow was the heaviest in 40 years. The course in Hangqi Banner, where the embankment collapsed, now holds 450 million cubic meters of water, 50 percent more than in a normal year.

    In efforts to alleviate the flood caused by ice blockage, the region deployed its first ever water diversion on the river on March 10 through a primary drainage canal in rural Hetao area, to nearby Wuliangsu Lake.

    Troops blasted the Qingshuihe section, downstream from the collapsed area, to clear accumulated ice blocks threatening lives and property on March 14.