Israel has drones that can drop bombs silently from the sky with no smoke, making them difficult for their targets to detect, a senior military officer has said.
The source spoke to Reuters in a rare discussion about the capability of the country's advanced but secretive drone programme.
"No one will hear it, no one will see it coming," the source said.
Israel is believed to have one of the world's most-advanced unmanned aerial vehicle (UAV) systems but actual figures about the number of drones it has are closely guarded.
However, the insight into their capability comes as Iran accused Israel of using drones to carry out an attack on one of Tehran's own UAV warehouses in the province of Isfahan last weekend.
The source said Israel has an armed drone the size of a passenger plane able to operate at vast distances.
The Heron TP is made by Israel Aerospace Industries and is the military's "heaviest drone", with the ability to "carry munitions with an effective payload of around a tonne".
The munitions themselves are also Israeli-made, the officer said, and can "reach the speed of sound" upon free-fall.
Other UAVs which can be armed include the Hermes 450 and Hermes 900, the British Royal United Services Institute (Rusi) defence think tank has reported.
Israel accounted for more than 60 per cent of global UAV exports in 2017, Rusi said.
The Israeli military official said these sales are government-to-government only.
Israel began its UAV programme after the 1973 Yom Kippur war with Egypt.
Two months after the Russian invasion of Ukraine last year, Germany approved the purchase of 140 Heron TP drones. The German Defence Ministry said at the time it was planning on using the majority for "operational use" and the remainder for training.
Israel's regional rival Iran has also admitted to supplying Russia with Iranian-made drones after initially denying the accusation made by the West.
Israel has tried to remain neutral in the Russian-Ukraine war but has supplied Ukraine with aid.