March 26 -- The Cheonan breaks in half and sinks in the West Sea after an unexplained explosion at 9:22 p.m. Of the 104 crewmen onboard, 58 are rescued, leaving the remaining 46 missing.
March 28 -- A rescue operation begins. The stern of the 1,200-ton frigate is located in waters 180 meters north of the explosion site.
March 30 -- Navy Warrant Officer Han Joo-ho dies after suffering from decompression sickness while conducting a rescue mission.
April 1 -- The military makes public video footage of the ship's sinking taken by an infrared thermal observation device. A geological survey institute confirms a man-made tremor with a magnitude of 1.5 on the Richter scale at the time of the ship's sinking.
April 2 -- The trawler Geumyang 98 sinks on its way back to port after taking part in rescue efforts for the ill-fated Cheonan. The bodies of two fishermen have been found, while the remaining seven are still missing.
April 3 -- The body of Senior Chief Petty Officer Nam Ki-hoon is found in the ship's galley in the wreckage. The families of the remaining missing sailors request the cessation of the rescue mission due to the life-threatening conditions the divers were facing.
April 7 -- Survivors from the sunken Cheonan hold a news conference, testifying that they heard two blasts.
April 15 -- The stern of the sunken warship is pulled out of the water and placed on a barge. The bodies of 38 sailors are retrieved from the salvaged hull.
April 17 -- North Korea makes its first official statement on the naval accident, flatly denying the growing speculation of its involvement in the sinking of the Cheonan.
April 22 -- The body of Petty Officer First Class Park Bo-ram is recovered from a funnel that broke apart from the warship.
April 24 -- The bow of the sunken ship is hoisted. The last body, identified as Petty Officer 1st Class Park Seong-gyun, is found.
April 25 -- A five-day national mourning period commences in memory of the fallen 46 sailors.
April 29 - A national funeral ceremony for the heroes takes place 35 days after the naval disaster.