As body after body is brought back to shore, the death toll from South Korea’s ferry disaster has risen to 87, with a further 215 people still missing.

Children account for most of those killed or presumed dead after the vessel capsized on a high school outing off the Korean Peninsula’s southwestern tip last Wednesday.

Six crew members have now been detained as well as Captain Lee Joon-seok, 69, who is accused of negligence.

It has emerged that in a promotional video four years ago, Lee said the journey from the port city of Incheon to the holiday island of Jeju was safe, as long as passengers followed the instructions of the crew.

It is a cruel irony for the families of victims.

Witnesses say the ferry turned sharply before it began listing and that although it took over two hours to fully capsize, passengers were told to stay put in their cabins. As is customary in hierarchical Korean society, the orders were not questioned.

Many of those who escaped alive either did not hear or flouted the instructions and were rescued as they abandoned ship.

South Korean President Park Geun-hye has slammed the conduct of the captain and some crew members as “tantamount to murder”.

Coastguard officials meanwhile say two US underwater drones have been deployed in the search for bodies. A US navy salvage ship is also on the way.