North Korea's state-run news agency said Saturday the country was struck by a massive flood in the northern part of the country, with 15 residents missing.

The Korean Central News Agency said this week's heavy rain led to the overflow of the Tumen River bordering China, resulting in "severe" damage in nearby cities.

It said 44,000 people in North Hamgyong Province were evacuated after their houses were damaged.

Fifteen others went missing in the northern city of Hoeryong, it added.

A source familiar with the matter earlier said a five-story apartment building collapsed in the communist nation's northern region after heavy rains and 34 people were killed.

North Korea said it will expand its look into the damage, indicating that reports of casualties and property damage may increase down the road. (Yonhap)