Fully autonomous drones with no human oversight have killed soldiers on the battlefield for the first time. This is according to a senior figure in the Ukrainian defence industry, marking a watershed moment in warfare.

The one-off test involved 10 AI-controlled “Terminator” drones on the front line of the Ukraine war. Russian soldiers were killed.

“We tried it,” says drone-maker Alexander Kokhanovskyy, who supplied the technology and spoke to New Scientist at a press event hosted by the Ukrainian embassy. “It’s a test. We never implemented it [more widely].”

The test took place two years ago and involved quadcopter drones that were programmed to fly towards the front line, cover between 3 and 5 kilometres over around 10 minutes and then engage “Terminator mode”, in which an AI model searches for and intercepts targets.

“We just launch it and we know everything will be dead – everything that will be found there in this particular area will be dead,” says Kokhanovskyy. “There is no connection to the drone at all, you cannot see the video, nothing… Everything it sees will be killed.”

With no way to tell what the automated drones had seen or targeted, human-piloted drones were sent into the area after the test to manually check results. Victims included “a couple of soldiers, one truck”, says Kokhanovskyy. While there is no recording of the automated drones attacking these targets, it was concluded that the drones had killed them.

Kokhanovskyy says that he was not at the test personally but that it was carried out by an unnamed military unit near the cities of Bakhmut and Chasiv Yar as part of a Ukrainian counteroffensive push. The Ukrainian Ministry of Defence did not respond to questions about the test or the current legal position on the use of fully autonomous weapons.

The use of AI is common in militaries around the world, helping to pick targets among overwhelming piles of intelligence data and automating certain functions of weapons, but humans are always in the loop at some point. Kokhanovskyy’s admission is the most categorical evidence yet that a death has occurred in battle solely at the hands of AI.

The Ukrainian government currently bans the use of AI at the final stage of intercepting targets, according to defence company sources speaking at the embassy press conference, although AI is used for many parts of the process by many devices up to that point. Kokhanovskyy says that the government is aware of the growing capabilities of AI and that it is in talks with defence companies about whether or not rules should be made more lenient.

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