The United States on Thursday released a video it said shows an “unsafe” and “unprofessional” intercept by Russian military jets when one struck an American drone, damaging its propeller.

Russia has denied responsibility for the incident, which the United States says left its drone uncontrollable and required it to be brought down in the Black Sea.

The declassified 42-second video — which the US military says has been edited for length — shows an Su-27 jet bearing down on the propeller-driven MQ-9, releasing streams of fuel as it passes in an apparent effort to harass the drone.

An Su-27 makes another pass, again dumping fuel as it does so.

The video is then interrupted — a cut the US military said lasts for 60 seconds due to a Russian jet striking the drone. When the feed returns, part of the drone’s propeller is missing.

Russia’s defense ministry said it had scrambled jets on Tuesday after detecting a US drone over the Black Sea but denied causing the crash, saying the aircraft had lost control.

The Pentagon said the drone was on a routine mission when it was intercepted — a term that refers to one aircraft making visual or electronic contact with another — in a “reckless” and “unprofessional manner.”

The incident has ratcheted up tensions between Moscow and Western allies, already soaring over Russia’s invasion of Ukraine, but top security officials from the United States and Russia have been in touch.

Maintaining Communications

US Defense Secretary Lloyd Austin spoke with his Russian counterpart Sergei Shoigu on Wednesday, the Pentagon said, while Moscow’s defense ministry said General Staff Valery Gerasimov spoke to General Mark Milley, the chairman of the US Joint Chiefs of Staff.

“We take any potential for escalation very seriously and that’s why I believe it’s important to keep the lines of communication open,” Austin said after his call with Shoigu.

“I think it’s really key that we’re able to pick up the phone and engage each other. And I think that will help to prevent miscalculation going forward.”

Milley said Wednesday that it was unclear whether the collision was done on purpose, though the “aggressive behavior” was intentional.

Russia plans to try to retrieve the downed craft but was unsure if the effort would be a success.

Milley said the drone likely broke up and sank in an area where the water is 4,000-5,000 feet (1,200-1,500 meters) deep.

Even if Russia was able to recover the wreckage, the United States took “mitigating measures” to protect sensitive information and is “confident that whatever was of value is no longer of value,” he said.

The United States uses MQ-9s for both surveillance and strikes and has long operated over the Black Sea, keeping an eye on Russian naval forces.

Several of the drones have been lost in recent years, including one that the US Central Command said was shot down over Yemen with a surface-to-air missile in 2019.