South Korea Ferry Rescue_Sewol
South Korean rescue workers operate near floats where the capsized passenger ship Sewol sank, during the search and rescue operation as a giant offshore crane, which will take part in the rescue operation, is seen in the background in the sea off Jindo on April 21, 2014. Reuters/Kim Hong-Ji

SEOUL (Reuters) -- South Korean prosecutors investigating the fatal sinking of the Sewol ferry raided Wednesday the home of Yoo Byung-un, the head of a family that owns the Chonghaejin Marine Co. Ltd, which operated the vessel.

Yonhap news agency reported that Yoo's home and a church in which he is believed to have an interest were raided. The prosecutors' office declined to comment and Reuters correspondents at the church in Seoul said it had been locked.

The finances of Chonghaejin and its complex share structure have come into the spotlight in recent days. Yoo was jailed for fraud for four years in the early 1990s.

Last Wednesday's accident looks set to be South Korea's worst maritime disaster in 21 years in terms of loss of life.

The Sewol sank on a routine trip from the port of Incheon, near Seoul, to the southern island of Jeju.

Of the 476 passengers and crew on board, 339 were children and teachers on a high school outing. Only 174 people have been rescued and the remainder are all presumed to have drowned. The confirmed death toll on Wednesday was 128.

(Reporting by David Chance; Editing by Nick Macfie)