When Western researchers examined an Iranian drone downed over Ukraine this spring, they found a part that appeared to have been made in China in January.

Investigators said an Iranian drone brought down by Ukrainian forces in April contained a voltage converter that appeared to have been made in China in mid-January. It marks the first time a part made in 2023 has been found in the drones by researchers with Conflict Armament Research, a U.K.-based group that tracks global weapons supply chains.

The finding shows how quickly Iran can build and ship drones to Russia. The Chinese part was made in January, shipped to Iran, installed and then sent to Russia and used against Ukraine in April.The revelation shows that Chinese parts have continued to flow to Iran, providing the building blocks for its drone program, despite increasing pressure from the U.S. to choke off the global supply chain. And it demonstrates how quickly Iran is able to help Russia with its war in Ukraine, needing just three months to make and supply Moscow with weapons that have terrorized Ukraine’s civilian population.