Kathmandu, Nepal (CNN) -- The bodies of eight people were recovered Saturday after flash floods washed away a settlement in central Nepal, police said.
It is unknown how many people were missing after the sudden, unexpected flooding of the snow-fed Seti Gandaki River near Pokhara, Nepal's second largest city, said Sailesh Thapa, the police superintendent of the Kaski district, about 200 kilometers west of Kathmandu.
Three Ukrainians, believed to be tourists, were among the missing, he said.
"A settlement has been washed away by a river in the mountains and rescue efforts are underway," Thapa said.
The flooding was believed to have been triggered by an avalanche in the mountains or a glacial lake outburst flood, possibly triggered by the erosion of glacier ice, Thapa said.
A helicopter has dispatched to the area to find out the cause of the floods, he said.