A South Korean fisheries official went missing earlier this week while on duty aboard an inspection vessel near the border island of Yeonpyeong and authorities are looking into reports he may be in North Korea.

The Defense Ministry said Wednesday the Coast Guard was alerted on noon Monday that the Oceans and Fisheries Ministry official disappeared from the boat, leaving behind only his shoes, in the West Sea about two kilometers south of Soyeonpyeong Island. 

According to military intelligence, the ministry said he may have been found in North Korean waters on Tuesday. Officials are investigating how he went missing and are verifying related facts with North Korea.

Authorities believe that the 47-year-old official is still alive.

The military and police conducted search operations on Monday, deploying around 20 ships and aircraft. They are considering the possibility that currents swept him into North Korean waters or that he defected. If he is confirmed to be in the North, South Korea will likely request repatriation.