Although the Cold War is technically over, the US and Russia are adversaries on multiple fronts, and rarely seem to get along. Space was one of the few exceptions — for the most part, at least. But things are getting tense on the International Space Station (ISS) too.

In an unsubstantiated article by Russia’s state-owned news agency TASS, a “high-ranking,” anonymous employee of Russia’s space agency Roscosmos accused US astronaut Serena Auñon-Chancellor of deliberately sabotaging the station.

The article in Russian seeks to address criticisms of the recent Nauka incident, and the Russian space program in general, and at one point, the article makes a special mention of an event from a Soyuz spacecraft in 2018, when an air leak was observed at the orbiting laboratory. The Russian mouthpiece accused Auñon-Chancellor of drilling a hole herself in the ISS’s Soyuz MS-09 vehicle.

The reasoning, the unnamed official claims, is that the American astronaut suffered a “psychological crisis” after experiencing a deep vein thrombosis (blood clot in the internal jugular vein of their neck). The article doesn’t offer any evidence but goes on to claim that American astronauts refused a polygraph test and the video camera at the junction of the Russian and American segments did not work at that time.

Obviously, suffering from a medical condition while orbiting the Earth in a research module is far from ideal. But from this to sabotaging a module just so you can get home earlier is a very big leap. Without any evidence and nothing more than an anonymous accusation, few were really convinced. NASA also wasn’t having it.

“NASA astronauts, including Serena Auñón-Chancellor, are extremely well-respected, serve their country, and make invaluable contributions to the agency,” Kathy Lueders, chief of human spaceflight for NASA, tweeted on Friday. “We stand behind Serena and her professional conduct. We do not believe there is any credibility to these accusations.”

NASA Administrator Bill Nelson followed up, adding: “I whole-heartedly agree with Kathy’s statement. I fully support Serena and I will always stand behind our astronauts.”

However, NASA also didn’t publish an official statement clarifying the situation, and the one they did doesn’t directly exonerate the US astronaut.

“To protect their privacy, the agency will not discuss medical information regarding crew members.”

Perhaps, as Ars so eloquently put it, NASA just wanted to avoid a pissing match with Rocosmos, or simply thought it beneath them to flat out deny something as crazy as an astronaut sabotaging a module. But the spat is unlikely to be a minor incident.

America’s and Russia’s space efforts are drifting further and further apart, with Russia planning to withdraw from the ISS and teaming up with China to build a new station.