The US intelligence community is warning the domestic space industry of the growing risk of espionage and satellite attacks from China, Russia and other adversaries.

US space-related companies are at risk of “cyberattacks, strategic investment (including joint ventures and acquisitions), the targeting of key supply chain nodes and other techniques to gain access to the space industry,” says a bulletin issued jointly by the National Counterintelligence and Security Center, the Federal Bureau of Investigation and the US Air Force on Friday.

The warning, which says such foreign intelligence operations pose a risk to company secrets as well as “disrupting and degrading US satellite communications, remote sensing and imaging capabilities” comes after several recent attacks on satellites and mounting recognition that both the US economy and national security increasingly rely on space.

The warning advises companies to log anomalies, establish an insider-threat program to hunt out moles and be wary of requests to visit from foreign entities and of outreaches at conferences and online. It also warns about “unsolicited offers to establish joint ventures with companies tied to foreign governments or state-owned enterprises.”

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China and Russia historically dismiss allegations they have carried out hacking and other attempts to infiltrate or disrupt space systems. The Chinese and Russian embassies in Washington didn’t immediately respond to a request for comment.

The US is particularly keen to support medium and smaller satellite companies that may not be aware of the scale and types of risks and to help them boost their own mitigation efforts and resilience, according to a US counterintelligence official who requested anonymity to share details.

Large satellite companies with existing links to government have already been targeted too. Viasat Inc. suffered a 2022 cyberattack ahead of Russia’s invasion of Ukraine that saw the company replace more than 45,000 modems across Europe and beyond. Starlink, part of Space Exploration Technologies Corp., known as SpaceX, has stated that it’s faced jamming attacks as part of its effort to provide service to Ukraine.

US Space Force this month unveiled a new targeting unit focused on adversaries in space and at ground stations and the threats they pose to US satellite systems in space.