Map showing the crash site of the American “drone” in the Black Sea

LONDON, UK (CNN) — The United States released footage of the moment a Russian jet dumped fuel on a US drone over the Black Sea on Tuesday, a confrontation that has sparked a diplomatic row and led to a race to get back some of its top-secret technology.

The incident marks the first known incident of Russian and US military aircraft in direct physical contact since Russia launched its invasion of Ukraine just over a year ago, and is likely to increase tensions between the two countries.

Most urgently, the race is on to avoid the drone falling into the wrong hands.

The secretary of the Russian Security Council said on Wednesday that Russia might try to obtain the wreckage of the drone for study, and the Kremlin said the decision to retrieve the drone from the Black Sea would come from the Russian Defense Ministry.

On Thursday, the Ukrainian Operations Command said, in a post on its official Facebook page, that Russia is increasing its presence in the Black Sea with a “somewhat unusual number of ships”.

Operations Command “Southern”: “The somewhat unusual number of ships of 21 units may be related to the display of dominance at sea,” after the drone incident on Tuesday.

“It is also possible that the Russians themselves are conducting a search,” she added.

Here is a look at the infographic above on a timeline up to the moment the American “drone” crashed in the Black Sea.