A funeral took place in Incheon on Monday for coast guard officer Lee Jae-seok who died last Thursday while saving a senior citizen who was stranded at tidal mudflats. 

Lee set out alone to rescue a man in his 70s who became stranded in tidal mudflats in Incheon's Ongjin County in the early hours of Thursday. The man survived thanks to Lee's life jacket, but Lee got swept by the tide and was found dead six hours after going missing.

The Korea Coast Guard launched an investigation Monday into Lee's reasons for embarking on the rescue operation on his own and whether there were problems with the Incheon coast guard's handling of Lee's case.

During a news conference earlier in the day, Lee’s fellow officers said it was incomprehensible why Lee had gone on the mission alone, claiming that no rescue order had been issued and that the Korea Coast Guard was trying to hide the truth behind Lee’s death. 

The coast guard in Incheon denied the allegations, saying it would shed light on Lee’s death by cooperating with the Korea Coast Guard's investigation.