Holding hands as they walked through the school gates, some fighting back tears, 75 children who survived South Korea's worst maritime disaster in 20 years returned to class on Wednesday pledging to remember their lost friends.

Wailing parents of the 250 children who did not survive, when a ferry taking them on a school trip capsized and sank, greeted the children outside the Danwon High School.

Some grieving parents held signs, one of which read: "We love you."