Authorities in Kazakhstan have detained five Defence Ministry officials including the first deputy navy commander, a day after 14 servicemen were swept out to sea and died during a training exercise.
The incident happened on Thursday when military personnel were disembarking from a patrol boat on the Caspian Sea coast in rough weather.
Three other people were rescued after being thrown into the water.
The Interior Ministry said the five senior officials had been detained on suspicion of negligence and violations of navigation rules.
Investigators were examining the decisions taken by those arrested, their adherence to safety rules and whether they had taken proper account of the weather conditions, as well as the technical state of the boat.
Kazakhstan has a small navy of about 3,000 personnel based on the Caspian Sea, operating patrol and missile boats to protect its maritime border and offshore energy infrastructure.
President Kassym-Jomart Tokayev has declared Friday a nationwide day of mourning in the Central Asian state.

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