There was a loud impact and noise before the ferry off a coast of South Korea began sinking, a passenger who had been rescued from the vessel told YTN news television.
One person has been found dead in the ferry wreckage, according to a coast guard official.
The president of South Korea, Park Geun-hye, earlier ordered all available vessels and special operations divers to the rescue operation.
More top news
The former presidential candidate, who has herself been the target of false news reports, said such stories had 'real-world consequences'.
London councils recorded the largest surpluses, with the capital's 33 local authorities accounting for 44% of the total figure.
Outbreaks of rain will move slowly from north to west but otherwise a mainly dry day ahead.