The Israeli air force is adapting some of its systems and adding others, to be ready for a wide unmanned air systems attack on targets inside the country in a future military confrontation.
The service pointed to the threat for the first time when Brig Gen Shachar Shohat, head of its defence command, addressed a conference in Tel Aviv in mid-March.
UAS flew into Israeli airspace from Lebanon on at least two occasions in 2012 and 2013, apparently on photography missions and in attempt to probe air defences. Both were shot down by air force fighter aircraft.
Israeli sources say the threat, especially from Lebanon, may range from radio-controlled drones carrying a small explosive load to UAS carrying payloads of hundreds of kilogrammes. According to well informed sources, Israel believes that the Hezbollah organisation in Lebanon has already received some heavy UAS made in Iran.
Preparing the air force to respond to such platforms includes the use of systems that can detects small UAS before they cross the border, and others that can shoot them down immediately after detection.
While the main UAS threat is from Lebanon, the air force also takes into account a similar threat from the Gaza strip. At this stage Hamas militants are using rockets, but Iran may potentially also try to supply some types of unmanned aircraft to the organisation, sources suggest.
On 12 March, 50 rockets were launched into Israel from Gaza. Some with a "lethal trajectory" were intercepted by the Iron Dome air-defence system. In response, the Israeli air force attacked 29 targets inside the Gaza strip.