At least 14 Kazakh military personnel were killed after being swept away during a naval exercise on Thursday. Following the incident, the authorities detained five defence officials on Friday.On Thursday, at least 17 servicemen were washed away in the Caspian Sea as they were disembarking from a patrol boat during a military exercise. Authorities reported that three were eventually rescued.The defence ministry said that it had concluded search and rescue efforts following the incident.“The leadership and personnel of the ministry of defense and the armed forces of the Republic of Kazakhstan extend their deepest and most sincere condolences to the families and loved ones of the deceased servicemen,” the ministry said on Telegram.“The families of the fallen will receive all necessary comprehensive, financial, and psychological support,” it added.The exercise was reportedly being conducted during rough weather conditions over the sea.Anadolu Agency reported that the incident occurred “due to a sudden deterioration in weather conditions and intensifying winds,” and a commission led by defense minister Dauren Kosanov was immediately deployed to investigate the incident.According to the interior ministry, five military officials, including the first deputy navy commander, have been detained over allegations of negligence and navigation rule violations.Additionally, authorities reported that the decisions of detained military officials were being investigated, with the weather conditions and technical state of the boat being taken into accountKazakh President Kassym-Jomart Tokayev declared Friday a nationwide day of mourning, expressing deep condolences.According to Reuters, Kazakhstan operates a small navy of about 3,000 personnel in the Caspian Sea and operates patrol and missile boats to protect its maritime border and offshore energy infrastructure.