The U.S. Army has ordered units to cease the use of DJI drones, according to a memo obtained by sUAS News.

The letter, dated this week, said the U.S. Army Research Lab and U.S. Navy found there were operational risks linked to DJI equipments. Officials cited a classified report called “DJI UAS Technology Threat and User Vulnerabilities,” as well as a U.S. Navy memorandum called “Operational Risks with Regards to DJI Family of Products.” The report and the memo were both dated May 2017, which suggests officials have been looking into this for a while.

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In the letter, the U.S. Army’s Lieutenant General Joseph Anderson said:

"DJI Unmanned Aircraft Systems [UAS] products are the most widely used non-program of record commercial off-the-shelf UAS employed by the Army. The Army Aviation Engineering Directorate has issued over 300 separate Airworthiness Releases for DJI products in support of multiple organisations with a variety of mission sets. Due to increased awareness of cyber vulnerabilities associated with DJI products, it is directed that the US Army halt use of all DJI products."

The Army ordered its units to halt the use of DJI products, including all of the company’s unmanned aerial vehicles (UAV). The rule also applies to other items from the manufacturer, including flight computers, cameras, radios, batteries, speed controllers, GPS units, handheld control stations, and devices with DJI software applications installed. Officials also directed members to uninstall all DJI applications, remove battery and storage media from devices and to secure all equipment.

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DJI told International Business Times it was surprised about the Army’s decision.

The company said in a statement:

“People, businesses and governments around the world rely on DJI's products and technology for a variety of uses including sensitive and mission critical operations. The Department of the Army memo even reports that they have ‘issued over 300 separate Airworthiness Releases for DJI products in support of multiple organizations with a variety of mission sets.’

We are surprised and disappointed to read reports of the U.S. Army’s unprompted restriction on DJI drones as we were not consulted during their decision. We are happy to work directly with any organization, including the U.S. Army, that has concerns about our management of cyber issues.”

DJI said it planned to reach out to the U.S. Army to confirm the memo and to get to the bottom of that they meant by “cyber vulnerabilities.”

There have been some cybersecurity concerns regarding drones, as some people attempted to hack DJI's Go app and firmware. Others have expressed privacy concerns regarding data collection, as reports claimed DJI shared information with Chinese authorities.

“We want to emphasize that DJI does not routinely share customer information or drone video with Chinese authorities — or any authorities,” the company clarified last year.

The manufacturer added:

“DJI complies with national laws wherever we operate, and we urge our customers to do the same. If one of our drones is implicated in a potentially illegal flight, authorities in any country may seek flight data information from us as part of their investigation. Like other tech companies around the world, we would consider only valid legal requests on a case-by-case basis and would provide information if we believed it was necessary to comply. Unless a customer has chosen to sync flight data via the DJI GO app or sent the aircraft back to DJI, we would have no flight data to provide.”