Seoul, Aug 13 (IANS): Significant flooding has taken place along a river near North Korea's Yongbyon nuclear complex, and facilities could have been damaged as a result, a monitoring website said on Thursday.

The Washington-based website 38 North, a think tank monitoring North Korea, made the analysis based on satellite imagery from August 6, saying that "water had reached the two pump houses that service the reactors" at the Yongbyon nuclear complex, reports Yonhap News Agency.

"The August 6 imagery, when compared to imagery from July 22, shows a dramatic rise in the water level of the Kuryong River that flows alongside the Yongbyon complex," the think tank said.

It said the flooding appears to be the worst in recent years.

The website also revealed an image of a fully submerged dam on the Kuryong River and pointed out that the flood could potentially damage the pumps or clog piping systems that draw water from the river, causing the reactor to shutdown.

South Korea's Defence Ministry has however, declined to confirm the report.

"Our military is always closely monitoring the North's nuclear and missile activities, and the authorities of South Korea and the US are keeping a close cooperation system," Yonhap News Agency quoted Deputy Ministry spokesperson Col. Moon Hong-sik as saying at a press briefing here.

The complex is home to a 5-megawatt nuclear reactor that was the source of weapons-grade plutonium for the North.

Pyongyang can harvest one nuclear bomb worth of plutonium by reprocessing spent fuel rods from the reactor.