The US on Friday added five Chinese companies and one research institute connected to Beijing’s aerospace programs including airships and balloons to an export blacklist.

The Commerce Department said the six entities were supporting “China’s military modernization efforts, specifically the People’s Liberation Army’s (PLA) aerospace programs including airships and balloons.”

The six companies are 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. along with Shanxi Eagles Men Aviation Science and Technology Group Co.

These latest sanctions come a day after the US Congress unanimously condemned China’s alleged use of a spy balloon that flew over North America last weekend. China said it was a “weather balloon.”

The balloon was shot down by a highly advanced US fighter jet last week. President Joe Biden congratulated US fighter pilots for taking down the balloon in the country’s airspace and above its territorial waters. The Pentagon decried what it called China’s unacceptable violation of US airspace. China has expressed regret blaming unfavorable winds for pushing what it calls a “civilian airship” into US airspace. Beijing China insists the balloon was a “civilian airship used for research, mainly meteorological purposes,” and it unintentionally veered off into us airspace.

The incident prompted US Secretary of State Anthony Blinken to issue a personal note to his Chinese counterpart condemning Beijing’s move. Companies added to the so-called Entity List are restricted from acquiring US items and technologies without government authorization. “The (People’s Republic of China’s) use of high-altitude balloons violates our sovereignty and threatens US national security,” said Under Secretary of Commerce for Industry and Security Alan Estevez in a statement on Friday.

“Today’s action makes clear that entities that seek to harm US national security and sovereignty will be cut off from accessing US technologies,” he added. The Commerce Department alleged in a document that China’s military is utilizing high-altitude balloons “for intelligence and reconnaissance activities,” adding that this was contrary to US national security and foreign policy interests. Beijing on Sunday blasted the Pentagon’s decision to shoot down the balloon spotted flying over North America, accusing the United States of “clearly overreacting and seriously violating international practice”.

“China expresses strong dissatisfaction and protests against the use of force by the United States to attack the unmanned civilian airship,” the Chinese foreign ministry said in a statement, adding that it would “reserve the right to make further necessary responses”. The Chinese foreign ministry said it had “clearly requested that the United States properly handle the matter in a calm, professional, and restrained manner”.

Beijing said the United States “insisted on using force, clearly overreacting and seriously violating international practice”. “China will resolutely safeguard the legitimate rights and interests of relevant enterprises and reserve the right to make further necessary responses,” the ministry said in its statement.

More than 600 sanctioned entities in China

According to The Wall Street Journal, more than 600 entities and companies related to the Chinese government have been sanctioned by the United States thus far.

The Bureau of Industry and Security of the U.S. Department of Commerce pointed out that the People’s Liberation Army uses high-altitude balloons for intelligence and reconnaissance activities.

Matthew Axelrod, the Assistant Secretary for Export Enforcement of the Department, said that the inclusion of six Chinese companies in the Entity List shows that the various departments of the U.S. government will work together to identify and dismantle China’s use of surveillance balloons to violate the airspace of the United States and more than 40 other countries;

Deputy Commerce Secretary Don Graves said that the Department of Commerce “is using the Entity List and other regulatory and enforcement tools to protect the United States. National security and sovereignty without hesitation.”