An Israeli air force Elbit Systems Hermes 450 unmanned air vehicle crashed into the sea off the coast of Ashkelon on 8 October, after its operators had noticed an engine problem.
The wreckage was picked up by the Israeli navy shortly after the incident.
The Hermes 450 had taken off from the air force's Palmachim air base on a routine mission. The service operates the surveillance type over the Gaza Strip in a variety of missions.
The mishap represents the second loss of a Hermes 450 within recent months. On 14 July, the air force performed a planned crash landing with another airframe near the Israeli border with Egypt, after its operators detected a malfunction which might have caused an uncontrolled crash later. The UAV's debris was picked up by a special unit.
Unlike in the earlier crash, the latest accident was caused by a sudden technical problem. An investigation that began hours after the incident will try to establish the exact cause.