Israeli jets scrambled to intercept a drone that crossed into Israeli airspace from the Mediterranean Sea, bringing it down without incident in the south of the country, a military spokeswoman said.

Lieutenant-Colonel Avital Leibovich said Israeli systems on the ground alerted the air force to the drone Saturday morning. She said it flew over the Gaza Strip but did not originate from the Palestinian territory.

She said Israel did not know the drone's starting point and an investigation was under way. Nobody was hurt in the incident.

Leibovich did not give more details, but Israel media reported that the aircraft was not carrying explosives and could have been a surveillance drone.

Leibovich said the operation was successful and the military was in control throughout.

"We had monitoring contact from the ground and from the air," she said.

"We alerted jet planes that escorted the unmanned aerial vehicle and due to some operational considerations we decided to intercept the unmanned aerial vehicle in the northern Negev area, which has no population."

It is not the first time that Israel has shot down drones entering its airspace, but such cases are rare. The Lebanese group Hezbollah has launched several such aircrafts into Israel over the past few years.

In the 2006 war, Hezbollah launched an Iranian-made drone capable of carrying explosives into Israel that was shot down. 

Another drone two years earlier crashed in the Mediterranean.

Leibovich would not elaborate how the unmanned vehicle was brought down.

She said troops were searching for debris from the drone.

Ehud Barak, the defence minister, congratulated the military.

"We view this incident of attempting to enter Israeli airspace very severely and we will consider our response later," he said in a statement.