Photo/Illutration A part of a main road near the Han River is flooded due to heavy rain in Seoul on Aug. 6. (AP Photo)

SEOUL--A massive search was under way in South Korea on Thursday after one rescue worker was killed and five went missing when their boats overturned and were swept over a dam by surging floodwaters, Yonhap news agency reported.

Parts of South Korea have seen 44 consecutive days of rain, the longest monsoon since 2013, and continued showers across the Korean Peninsula threatened to bring new floods and landslides.

Two rescue boats were trying to free a police boat stuck in wire by a dam near the city of Chuncheon, to the northeast of Seoul, when they overturned, Yonhap reported.

One man was rescued at the scene, but seven others were swept over the dam’s floodgates.

One of the seven, a 68-year-old man, was found near the dam suffering from cardiac arrest but was recovering. Another, also 68, was recovered dead about 20 kilometers downstream, Yonhap reported.

A local police official told Reuters he was busy with the search but could not confirm the details.

More than 800 police and fire officials, seven helicopters and 69 boats were dispatched to the scene to search for the remaining missing people, according to media reports.

Elsewhere, at least 16 people have been killed and 11 were missing, with more than 1,600 people displaced over recent days.

In Seoul, the Han River swelled over its banks in some areas after authorities were forced to open floodgates on upstream dams. Some highways by the river had to be closed, Yonhap reported.

On Wednesday, Prime Minister Chung Sye-kyun visited some of the hardest-hit areas and urged the government to consider designating several provinces special disaster zones.

A decision on that could come by Friday, Yonhap reported, with the designation enabling more government aid.

Emergency workers implemented measures to prevent the spread of the coronavirus in gyms and community centers being used as shelters.

Heavy rain has also fallen in North Korea and state media published pictures of flooded streets but did not give any detail of damage or casualties.

The government in North Korea had issued a flooding alert for areas near some its biggest rivers and lakes, the Rodong Sinmun newspaper reported.