“Come back to us now. Your mother is waiting for you,” he said before tossing a flower overboard, in an event that was broadcast live online.

A crowd of some 2,500 mourners took part in a memorial service at Jindo, reading memorial poems and releasing thousands of yellow balloons into the air in remembrance of the victims.

Memorial events also took place in Seoul and in Ansan, where the students studied.

Following the disaster, it emerged it was primarily caused by human error – an illegal redesign, overloaded cargo bay, inexperienced crew and a questionable relationship between operators and state regulators.

Seoul announced last year that it would raise the 6,825-tonne ferry, which had been a key demand of the victims’ families, who cling to hopes that nine bodies still unaccounted for may yet be recovered.

The US$72 million project to raise the vessel is being spearheaded by a Chinese company. It is expected to begin next month and could be finished by late July.

“The government will do its best to salvage the ship and bring back the nine missing bodies safely to the families,” Oceans Minister Kim Young-suk said at the memorial service at Jindo.

The Sewol lies more than 40 metres beneath the sea’s surface, and officials say lifting the 145-metre-long vessel from the seabed without splitting it into sections first will be the main challenge.

“Unfortunately, nothing can be guaranteed and we can only do the very best we can do to ensure that the risk is minimised,” said Simon Burthem, a naval architect at TMC, a global consulting firm involved in the salvage project.

Still, he said there was an 80 per cent chance the operation would succeed.

“Lifting the wreck in one piece from such a depth has never been done before, so this is a very, very difficult and challenging project and indeed a world first,” he said.

Wang Weiping, the site superintendent of the Chinese salvage company, praised the dangerous work required by dive teams in often treacherous conditions ahead of the planned ship recovery.

Their main task had been to seal the vessel’s with netting to ensure nothing – such as human remains – tumbles out when the ship is being lifted.

For the families of the nine victims whose bodies were never recovered, the two-year wait has been emotionally draining.

“It’s been 730 days and I can see the ocean before me,” said Lee Keum-hui, who has been camping out at Paengmok harbour near the salvage site, praying for the recovery of her 16-year-old daughter’s body. “I know where she is but I can’t get her.

“I know the government can do more. But all I can do is just wait and trust its words.”

Other bereaved family members accused the government of a lack of transparency.

“Everything is conducted behind closed doors and the families are not permitted to observe the recovery operation,” said Jung Seong-wook, who acts as a families’ representative for the salvage project.

The maritime ministry says it can arrange trips for the families as long as they do not “disrupt salvage operations,” stressing the need for “intense concentration” at what they call a critical time.

For relatives like Lee, the prospect of not recovering victims’ remains is almost unbearable.

“We tremble with fear at even the slightest chance of never finding the missing bodies,” she said.