A small police plane crashed into the sea near a popular beach town in Thailand, killing at least five people on board, officials said. The plane was conducting a test flight to prepare for parachute training in Hua Hin district before it crashed around 8 a.m., said Royal Thai Police spokesperson Archayon Kraithong. Officials did not immediately share the model of the propeller plane, but photos from the scene appear to show a Viking DHC-6 Twin Otter. The plane crashed near Hua Hin Airport, said the public relations department of Prachuap Khiri Khan province. The photos show the plane in the sea about 100 meters (330 feet) offshore. The body of the plane appeared to be broken in two. There were six people on board, all police officers, Archayon said. He initially said that five people died at the scene and one died at the hospital, but later revised the death toll to five, saying the officer who was sent to the hospital remained in critical condition but alive. The cause of the crash was not immediately known. Archayon said officials are gathering evidence,e including data from the plane’s black box.