Police are investigating a horrific incident that occurred in South Korea when a man was crushed to death by an industrial robot that mistook him for a box of vegetables.

According to a Korean news agency, the victim, a worker in his 40s, was inspecting the robot’s sensor at a vegetable-packaging plant in South Gyeongsand province. The company uses collaborative robots or “cobots” to handle and package bell peppers and other vegetables for export to other Asian countries.

But one of these robot’s sensors malfunctioned, causing it to confuse the man for a box and grab him. The mechanical arm hurled the man against a conveyor belt, crushing his face and chest. Despite being rushed to the hospital, he died of head and chest injuries. Police have not released the victim’s name but said he was at the factory to inspect the robotic arm.

Authorities are investigating whether the robot had any technical defects or safety issues. One theory is that man may have inadvertently triggered the robot’s reaction by moving near it with a box in his hands. He could also have stood too close to the robot while carrying the box.

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Not the first time

Collaborative robots have been heralded for increased efficiency, reducing human errors, and boosting productivity. But incidents like the one in the vegetable plant raise concerns about their safety. Tragic mishaps have happened before. A robot at an auto parts factory crushed and seriously injured a worker last March, while another robot fatally crushed a worker at a milk factory the previous year, according to Fox News.