Islamic State fighters are posing a growing threat to US and Iraqi forces by deploying small commercial drones armed with improvised explosives devices or spy cameras that can evade detection, according to the Pentagon.

Islamic State fighters are posing a growing threat to US and Iraqi forces by deploying small commercial drones armed with improvised explosives devices or spy cameras that can evade detection, according to the Pentagon.

The threat led the Defense Department office charged with monitoring and countering improvised explosive devices to ask that Congress approve shifting $20 million to provide seed money for a counter-drone effort.

The Pentagon has requested congressional funding for a counter-drone effort CREDIT:MATT ROURKE/ASSOCIATED PRESS

The funds would bankroll moves to “identify, acquire, integrate and conduct testing” of technologies that would “counter the effects of unmanned aerial systems and the threats they pose to US forces,” according to a budget document sent to Congress last week. It was part of a request for approval to shift $2.5 billion in defense funds approved for this year from other purposes to reflect changing needs.

The request underscores that commercially available drone technology has proliferated beyond hobbyists to adversaries. In its latest annual report on Iran’s military capabilities, the Defense Department said the Islamic Republic is fielding armed drones among other “increasingly lethal weapon systems.” At the Pentagon, the police force has posted “no drone” signs around the sprawling complex along with the usual “no photos” reminders.

In the fight against Islamic State, “small and tactical unmanned aerial systems” equipped with improvised explosive devices, or IEDs, “pose a direct threat to US and coalition forces,” according to the budget document.

“Just days after the Iraqi forces began occupying Makhmour in Ninevah Province, a video surfaced” on an Islamic State web site “showing forces on the ground there, demonstrating they were using the footage in both reconnaissance and propaganda roles,” Army Colonel Chris Garver, the Defense Department’s top spokesman in Iraq, said in an e-mail.

The Joint Improvised-Threat Defeat Agency, the Pentagon office that has worked to combat improvised explosive devices since the 2003 Iraq war, has seen Islamic State fly “quadcopters and fixed-wing type drones you can buy commercially” as “both an IED delivery system and for reconnaissance,” its spokesman, David Small, said in an e-mail.

The commercial drones used by Islamic State have weighed about 50 pounds or less, he said. He didn’t provide details on the number of attacks or resulting casualties.

In addition to using drones with full-motion video to look for attack opportunities and to monitor Iraqi Security Forces, Mr Small said the pilotless aircraft are being used to provide target information for vehicles carrying suicide bombs.

Mr Small said “there is a wide array of technology angles we are looking into" to defeat the drones that would be deployed within two years, if not sooner.