China's State Oceanic Administration said four crew members were killed when a Marine Surveillance aircraft crashed in Zhoushan, East China's Zhejiang Province on Tuesday.
The plane was carrying a routine mission to monitor conditions in Zhejiang province whose coastline is dotted with hundreds of islands, the administration said in a statement on its website.
The type of plane was not identified, although the China Marine Surveillance agency operates aircraft including helicopters and the Chinese-made Harbin Y-12 turboprop, AP reported.
The administration said the wreckage was found early Tuesday evening after a search involving 18 ships and four helicopters. Two pilots and two enforcement officers were killed.