The Russian downing of a US drone over the Black Sea on Tuesday has sparked a diplomatic spat and a race to recover highly classified technology.

The White House criticized Moscow’s actions as “unsafe, unprofessional and reckless”, while Russia’s Defense Ministry denied that its plane came into contact with the drone.

Russian and American planes operated over the Black Sea during Moscow’s war in Ukraine, but this is the first such incident since the conflict began.

Here’s what you need to know.

What happened to the American drone?

The drone, a US-made MQ-9 Reaper, and two Russian Su-27 jets were flying over international waters over the Black Sea on Tuesday when one of the Russian planes intentionally flew in front of the UAV and dumped fuel on it. times, said a US European Command statement.

The aircraft then struck the drone’s propeller, causing the drone’s remote operators to shoot it down in international waters. Pentagon spokesman Brig. General Patrick Ryder added on Tuesday that the Russian plane flew “in the vicinity” of the drone for 30 to 40 minutes before crashing just after 7 a.m. Central European Time.

The Russians have given a different version of events. A Russian fighter jet “did not use airborne weapons or come into contact” with the drone over the Black Sea, the Russian Defense Ministry said in a statement on Tuesday.

The incident marks the first time Russian and US military planes have come into direct physical contact since Russia launched its invasion of Ukraine just over a year ago and is likely to escalate tensions between the two nations.

More pressingly, a race is on to prevent the drone from falling into the wrong hands. As of Tuesday night, neither country had recovered the drone, US officials said.

What is the MQ-9 Reaper drone?

The US Air Force primarily uses the Reaper for intelligence gathering, according to the service’s website, which touts the drone’s “intelligence, surveillance and reconnaissance” capabilities.

But when armed, the drone can also be used against “high-value, fleeting, time-sensitive” executive targets, given its weapon systems and ability to police an area over a long period of time.

In other words, the Reaper is capable of both guarding and attacking an enemy. These dual uses have earned the Reaper a nickname in military circles: the “hunter-killer.”

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