A sinkhole found near the National Assembly on June 19 / Yonhap



By Jung Min-ho

Sinkholes have appeared across Seoul, raising safety concerns. Yet investigators are struggling to explain what exactly caused them.

After three sinkholes were found in Songpa, southern Seoul, where the Lotte World Tower is under construction, some others were found in other parts of the nation's capital.

The latest one yawned open Thursday in front of the National Assembly in Yeouido. The hole, about one meter wide and one meter deep, is only 2 meters away from another one, which was discovered last month.

The Yeongdeungpo Police Station immediately started an investigation as soon as the first one was found on June 19. However, what they have found so far is little.

"We do not know the cause yet," an officer from the police station told The Korea Times. "In cooperation with Seoul Metro and Seoul Metropolitan Government, we investigated the problem and only found that the holes have nothing to do with sewerage."

The officer said the investigators are now looking more into water supply facilities and communication pipelines.

Some part of a roadway near Jeungmi Station, western Seoul, also collapsed on June 17, creating a hole 1.5 meter wide and 1 meter deep. Officials from Gangseo Police Station are still trying to figure out what caused it.

A sinkhole refers to any hole in the ground created by erosion, drainage of water or human activity.

For the holes in Songpa, where the Lotte World Tower is being built, some experts believed that the construction is responsible for creating the sinkholes.

However, the explanation is not enough for those created in other parts of Seoul.

No major incidents caused by the holes have been reported.