(Bloomberg) -- The US is adding six Chinese companies to an export blacklist over what it argues are links to a military-backed global balloon espionage program, the Commerce Department said, after a high-altitude balloon traversed the US before being shot down last week.

The six companies were added to the list for their links to the People’s Liberation Army aerospace programs “including airships and balloons and related materials and components,” the department said. It said the Chinese military is using high-altitude balloons “for intelligence and reconnaissance activities” that go against US national-security interests.

What the Balloon Saga Tells Us About China’s Spying: QuickTake

The designations were announced after the alleged Chinese spy balloon was identified over Montana last week before it transited the US and was shot down off the coast of South Carolina. China has insisted the balloon was a weather-monitoring device that blew off course, and has accused the US of over-hyping the episode.

President Joe Biden said the alleged espionage incident didn’t materially hurt US-China relations, but that it was a violation of US sovereignty and that the US would stand up for its national security against such threats. He’s come under fire from Republican lawmakers who said the balloon should have never been allowed to traverse the continental US for a week before it was shot down last Saturday.

The so-called entity list is a de facto export blacklist that only allows US exports when the government grants licenses. It wasn’t immediately clear how deeply the six companies are linked to US exporters or how much their operations will be affected by the designations.

The six companies were identified as Beijing Nanjiang Aerospace Technology Co., China Electronics Technology Group Corporation 48th Research Institute, Dongguan Lingkong Remote Sensing Technology Co., Eagles Men Aviation Science and Technology Group Co., Guangzhou Tian-Hai-Xiang Aviation Technology Co., and Shanxi Eagles Men Aviation Science and Technology Group Co.

(Updates with Commerce Department announcing sanctioned entities.)

©2023 Bloomberg L.P.