A special counsel investigation into the 2014 Sewol ferry sinking began a raid of Coast Guard headquarters in Incheon on Wednesday.

Prosecutors and investigators are known to have been dispatched to obtain records produced at the time of the disaster from the Coast Guard's search and rescue division. 

The raid could possibly continue for days depending on the progress.

Searches were also carried out on Monday at the Coast Guard's western regional headquarters and a branch in Mokpo. 

The special counsel probe was launched last month to investigate alleged evidence tampering related to security camera footage and digital video recorders salvaged from the ferry.