The wreck of the Sewol ferry, currently lying on its side at the southwestern port of Mokpo, is expected to placed in the upright position next month so search teams can carry out a detailed inspection of the vessel for the remains of people who have not been found, the Ministry of Oceans and Fisheries said Thursday.

The 6,825-ton vessel capsized and sank in waters off the southwestern tip of South Korea on April 16, 2014. The nation's worst maritime disaster in decades claimed 304 lives, mostly high school students on a school trip, and led to a yearslong salvage operation.

A consortium led by China's state-run Shanghai Salvage brought the ship to the surface in a complex operation and moved it to the port in March 2017. Workers have removed water and mud from the ship and have reinforced the structure following its yearslong submergence, authorities said.

Under existing plans, efforts will be made to get the Sewol upright on May 31, and the subsequent search of the ship should take about two weeks. Afterwards, an investigation of the hull will be carried out to determine the exact cause of the accident, a special  investigation committee said.