All 15 crew members involved in the navigation of the sunken South Korean ferry are being held after four more people were detained, the Associated Press reports.
Two members of the steering crew and two helmsmen were arrested today joining 11 others, including the ship's captain, who were previously detained.
They are accused of negligence and failing to help passengers in need as the ferry sank on April 16.
Some 187 bodies have been recovered from the vessel while 115 people remain missing.
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Last minute suspension of strike action has meant thousands of cancelled procedures will still not go ahead.
Children in the North and the Midlands are less likely to get a good secondary education than those in the South, schools inspector to say.
Mild in the south but colder in the north tonight and turning frosty and icy - before rain moves in.