The fishing vessel 'Seonchang-1' was carrying 22 people onboard, when it hit the 336-ton tanker 'Myeongjin-15' in Yellow Sea waters, near Yeongheung Island and capsized. As a result from the accident, 13 died, seven were rescued and sent to hospital for treatment, while two remain unaccounted for. The tanker is said to have sustained no damages.

Search and rescue forces have been searching the area for the two missing, without result so far, so more search vessels are expected to be involved in the operation. A total of 59 vessels, 15 airplanes and 59 divers will be mobilized offshore and some 1,380 people will search on shore, as bodies could have washed ashore, according to officials as cited by Yonhap news agency.

This is the second worst fishing vessel tragedy in South Korean waters in recent years, after a similar accident reported in September 2015, off Jeju Island, causing 15 people to die and three to go missing.

Local authorities are also investigating the root causes of the incident. The tanker's Captain and one more crew member were detained for questioning on charges of professional negligence resulting in death, sources say.