Salvage experts are preparing to raise the wreckage of a ferry that sank off the coast of South Korea nearly three years ago, killing 304 people, most of them children on a school trip. The Sewol was structurally unsound, overloaded and travelling too fast on a turn when it capsized and sank on 16 April 2014.

The vessel now lies at a depth of 44 metres (144 feet) on the bottom of the sea off the island of Jindo, and officials hope to find the last nine missing bodies. Of those killed, 250 were teenagers, many of whom obeyed instructions to remain in their cabins even as crew members were escaping the sinking vessel. Bereaved families have been calling for the ship to be raised. IBTimes UK looks back at the most powerful images of the South Korean Sewol ferry disaster.

Sewol ferry disaster 2014 South Korea
16 April 2014: The Sewol passenger ferry sinks off the coast of Jindo. Image provided by the Republic of Korea Coast Guard The Republic of Korea Coast Guard via Getty Images
Sewol ferry disaster 2014 South Korea
16 April 2014: A passenger is helped to safety by the Republic of Korea Coast GuardThe Republic of Korea Coast Guard via Getty Images
Sewol ferry disaster 2014 South Korea
16 April 2014: Passengers are rescued from the stricken ferry by the Republic of Korea Coast GuardThe Republic of Korea Coast Guard via Getty Images
Sewol ferry disaster 2014 South Korea
16 April 2014: Passengers are put into dinghies by the Republic of Korea Coast Guard from the ferry sinking off the coast of Jindo IslandThe Republic of Korea Coast Guard via Getty Images
Sewol ferry disaster 2014 South Korea
16 April 2014: The Republic of Korea Coast Guard airlift passengers from the ferry disasterThe Republic of Korea Coast Guard via Getty Images
Sewol ferry disaster 2014 South Korea
16 April 2014: The vessel, lying on its side, sinks off the coast of the island of Jindo, South KoreaThe Republic of Korea Coast Guard via Getty Images
Sewol ferry disaster 2014 South Korea
16 April 2014: Members of the Republic of Korea Coast Guard search for survivors as the Sewol ferry sinksThe Republic of Korea Coast Guard via Getty Images
Sewol ferry disaster 2014 South Korea
16 April 2014: The mother of a passenger who was on the ferry reacts as she finds her son at a gym in Jindo, where rescued passengers had gatheredKim Hong-Ji/Reuters
Sewol ferry disaster 2014 South Korea
16 April 2014: A relative waits for news of missing passengers at Jindo portChung Sung-Jun/Getty Images
Sewol ferry disaster 2014 South Korea
16 April 2014: Maritime police search for missing passengers of the Sewol ferry in the seaKim Hong-Ji/Reuters
Sewol ferry disaster 2014 South Korea
16 April 2014: Relatives of missing people look out to sea at Jindo, South KoreaChung Sung-Jun/Getty Images
Sewol ferry disaster 2014 South Korea
16 April 2014: The Sewol sinks into the sea, as flares are released for a night searchKim Hong-Ji/Reuters
Sewol ferry disaster 2014 South Korea
17 April 2014: Coast guard members search for passengers near a South Korean ferry that capsized on its way to Jeju island from IncheonEd Jones/AFP
Sewol ferry disaster 2014 South Korea
17 April 2014: Rescue boats sail around the Sewol passenger ship which sank, during a rescue operationKim Kyung-Hoon/Reuters
Sewol ferry disaster 2014 South Korea
17 April 2014: Rescue efforts continue around the upturned hull of the ferryChung Sung-Jun/Getty Images
Sewol ferry disaster 2014 South Korea
17 April 2014: A relative weeps as she waits for news of missing passengers at JindoChung Sung-Jun/Getty Images
Sewol ferry disaster 2014 South Korea
17 April 2014: People look out to see as the search for missing passengers, most of them schoolchildren, goes onEd Jones/AFP
Sewol ferry disaster 2014 South Korea
18 April 2014: A family member of a passenger onboard the Sewol ferry, closes her eyes at a port in Jindo, where family members gathered to wait for news from the rescue teamKim Hong-Ji/Reuters
Sewol ferry disaster 2014 South Korea
18 April 2014: Members from the South Korean Navy's Ship Salvage Unit (SSU) operate at the site of the capsized passenger ship SewolKim Hong-Ji/Reuters
Sewol ferry disaster 2014 South Korea
18 April 2014: A South Korean diver rests in the water during the rescue operation of the Sewol passenger ship, which capsizedKim Hong-Ji/Reuters
Sewol ferry disaster 2014 South Korea
18 April 2014: A Buddhist monk prays for the missing passengers who were on the Sewol ferry, at a port where family members of the missing have gathered in JindoIssei Kato/Reuters
Sewol ferry disaster 2014 South Korea
19 April 2014: A diver enters the water as the South Korean Navy searches for bodies at the site of the sunken ferryChung Sung-Jun/Getty Images
Sewol ferry disaster 2014 South Korea
19 April 2014: A body of a missing passenger of the Sewol ferry is carried by rescue workers from a coastguard ship to the landing pier at a port in Jindo , where family members of the missing passengers are gatheredIssei Kato/Reuters
Sewol ferry disaster 2014 South Korea
20 April 2014: South Korean rescue workers carry the bodies of passengers who were on the Sewol ferry at a port where family members of missing passengers gather in JindoIssei Kato/Reuters
Sewol ferry disaster 2014 South Korea
20 April 2014: An official uses a swab to collect DNA sample from a family member of a missing passenger onboard the sunken South Korean ferry Sewol in JindoKim Hong-Ji /Reuters
Sewol ferry disaster 2014 South Korea
20 April 2014: Relatives of victims of the ferry disaster look out to sea at Jindo harbourEd Jones/AFP
Sewol ferry disaster 2014 South Korea
21 April 2014: A girl holds her phone with a photo of her brother Cho Sung-won, one of the missing passengers, at a port where family members of missing passengers gathered in JindoIssei Kato/Reuters
Sewol ferry disaster 2014 South Korea
21 April 2014: A family member of a missing passenger prays at a port where family members of missing passengers gathered in JindoIssei Kato/Reuters
Sewol ferry disaster 2014 South Korea
21 April 2014: Relatives wait for news of missing passengers at Jindo gymnasiumChung Sung-Jun/Getty Images
Sewol ferry disaster 2014 South Korea
22 April 2014: South Korean rescue workers operate at sunset near floats where the Sewol ferry sankIssei Kato/Reuters
Sewol ferry disaster 2014 South Korea
23 April 2014: People holding candles pray for the safe return of missing passengers who were travelling aboard the ferry that sank off the coast of Jindo IslandChung Sung-Jun/Getty Images
Sewol ferry disaster 2014 South Korea
23 April 2014: Students from Danwon high school pay tribute at a group memorial altar at the Ansan Olympic Memorial HallChung Sung-Jun/Getty Images
Sewol ferry disaster 2014 South Korea
23 April 2014: South Koreans pay tribute at a group memorial altar for victims of the sunken passengers ferry at the Ansan Olympic Memorial HallChung Sung-Jun/Getty Images
Sewol ferry disaster 2014 South Korea
25 April 2014: A man offers prayers before the sea for victims of the Sewol ferry disaster at Jindo harbourEd Jones/AFP
Sewol ferry disaster 2014 South Korea
3 May 2014: A boy ties a yellow ribbon of hope onto a tribute to the victims of the sunken ferry in SeoulChung Sung-Jun/Getty Images

A Chinese salvage company has fitted 33 beams beneath the hull, and the system has been tested with 66 hydraulic jacks raising the hull one metre off the bottom, the Ministry of Oceans and Fisheries said. Divers are inspecting the progress.

"The vessel is slightly tilted and we need to even it out," Lee Cheol-jo, ministry official in charge of the operation, told reporters. If the ship can be levelled, and if the good weather holds, a decision could be made for the salvagers to go ahead and bring the ship up, the ministry said.