China reportedly provided Iran with high-resolution satellite imagery of a U.S. military base in Jordan shortly before an Iranian attack that killed three American service members, raising concerns about Beijing’s support for Tehran ahead of a planned summit between President Donald Trump and Chinese President Xi Jinping.

The imagery was obtained before and after Iran’s July 17 attack on Muwaffaq Salti Air Base in Jordan, according to the Wall Street Journal. U.S. officials have linked the imagery to the Iranian strike but have not publicly identified the Chinese entities involved or alleged that the Chinese government directly authorized the assistance.