Eleven days after the deadly sinking of the 6,825-ton ferry in southwestern waters, 187 of the 476 passengers aboard, most of whom were high school students on a field trip, have been confirmed dead and 115 others were still unaccounted for as of Sunday afternoon, they said.

The divers' search has been restricted by strong currents and limited visibility.

"Carpets, blankets, and furniture from different parts of the ship fill up passages and cabins, making it difficult for divers to enter," Kim Suk-kyoon, the chief of the Coast Guard, said.  He said the divers have not yet been able to work around the obstacles.

No bodies have been retrieved since early Saturday when divers found two more victims. Not a single survivor has so far been found among those missing.

Prosecutors said Sunday that they are looking into paper companies allegedly set up by the owner family of the operator of the ill-fated Sewol as part of their widening investigation into the cause of the deadly accident.

The prosecution suspects that Chonghaejin Marine Co., the ferry's operator, and Yoo Byung-eun, a billionaire whose family controls the firm, set up three paper companies to create slush funds.  They said the ship was found to have been poorly inspected.

"We've found at least three companies thought to be bogus firms, which are suspected of raising funds from affiliates under the pretense of consulting costs," an investigator said.

Meanwhile, a joint team of prosecutors and police officers have referred Sewol's disgraced captain Lee Joon-seok and two other crew members to the prosecution for further investigation on charges of neglecting their duties and abandoning the passengers.

All of the 15 crew members in charge of navigating the ship have been put behind bars, accused of failing to evacuate passengers from the sinking ship and not making efforts to save the passengers.

Thousands of people visited a memorial altar set up at a gym in Ansan, a city just outside Seoul, on Sunday to pay their respects to the more than 110 students and teachers confirmed dead.

Officials said more than 130,000 people have visited the altar over the past five days. (Yonhap)