The head of the operation to retrieve bodies from a sunken South Korean ferry admitted he had "no idea" when it would be over.

Furious relatives have accused recovery teams of dragging their feet.

In a briefing to reporters on the southern island of Jindo, Navy Captain Kim Jin-Hwang spoke of divers finding rooms crammed with up to 48 bodies during their search missions over the past week.

The confirmed death toll stands at 183, but 119 people remained unaccounted for.

It is believed their bodies are still trapped in the ferry that capsized on 16 April with 476 people on board.

Although all hope of finding survivors has been extinguished, there is still anger and deep frustration among relatives of the missing over the pace of the recovery operation off the southern island of Jindo.

Gentle tides and good weather have helped the dive teams in recent days.

However, the search conditions inside the ferry are still challenging and rescuers are only managing to retrieve around 30 bodies a day.

Many of the passengers on the 6,825-tonne Sewol were high school students.

Around 250 are either confirmed or presumed dead.

Mr Kim said his divers had found one dormitory room packed with the bodies of 48 students wearing lifejackets.

It would normally have held around 31 people.

He stressed that retrieving the bodies was far harder than finding them, with divers unable to spend much longer than ten minutes inside the ship at a time.

Many of the corridors are blocked by plywood boards and other debris and only one-third of the rooms on board have been accessed so far, he said.

"It's very stressful," Mr Kim said, adding that the divers were all too aware of the criticism from the families that they were not working hard enough.