The Tumen River, which serves as part of the border between China, Russia and North Korea, burst its banks late on Friday
Flooding caused by torrential rains hit North Korea this week, leaving 15 people missing and thousands of others homeless, according to Pyongyang's state media.
The Tumen River, which serves as part of the border between China, Russia and North Korea, burst its banks in "the worst-ever flood" in the area, the Korean Central News Agency (KCNA) said late Friday.
In the northeastern province of North Hamgyong, 15 people were missing in Hoeryong City and several counties including Musan, Yonsa and Onsong and part of the Rason special economic zone also suffered "serious damage".
More than 17,000 houses were destroyed or partly damaged, forcing 44,000 people to seek shelter elsewhere, KCNA said.
North Hamgyong Province received up to 32 centimetres (12 and a half inches) of rain between early Tuesday and mid-Friday, it said.
"Relentless campaigns are under way to stabilize people's livelihood and restore damaged properties", it said, adding that further assessments of the damage would continue.
North Korea is known for being vulnerable to natural disasters, especially floods.
Its territory is largely composed of mountains and hills that have long been deforested for fuel or turned into terraced rice fields, allowing rainwater to flow downhill unchecked, washing away top soil from agricultural fields.
A series of floods and droughts sparked a famine between 1994 and 1998 in the impoverished state, with economic mismanagement coupled with the loss of Soviet support exacerbating the situation.