SEOUL, April 21. /ITAR-TASS/. Fifteen more bodies have been recovered from the sunken South Korea’s Sewol ferry, raising the death toll to 80 people, Yonhap news agency reported. According to Yonhap, underwater robots have been employed in the search and rescue operation. The robots can work at night and in strong currents.

The robots are operated by two specialists from the US, and they are able to descend as deep as 3 km. South Korean robots lack sufficient capacity to counter the force of underwater currents, TV channel KBC reported.

Nearly 20% of the rescued schoolchildren require psychological counsel. One out of five people suffers from serious stress or depression, Korea University Ansan Hospital said. Eighty one survivors, including 74 students from Danwon High School, are receiving treatment in Ansan.