South Korean investigators said on Friday that life rafts and escape chutes on a sister ship to a sunken ferry were not working properly.
The Sewol ferry, weighing almost 7,000 tons, sank on a routine trip from the port of Incheon, near Seoul, to the southern holiday island of Jeju. Investigations are focused on human error and mechanical failure.
More than 300 people, most of them students and teachers from the Danwon High School near Seoul, are dead or missing presumed dead after the April 16 disaster. The confirmed death toll on Friday was 181.
Investigators seized a second ferry for checks belonging to the Chonghaejin Marine Co. (Reporting by Jack Kim; Editing by Nick Macfie and David Chance)