The U.S. Commerce Department said on Wednesday it was suspending the export privileges of three U.S.-based firms for 180 days for what it said was the illegal export of satellite, rocket and defense technology to China.

Quicksilver Manufacturing Inc, Rapid Cut LLC and U.S. Prototype Inc are subject to the action for the unauthorized export of technical drawings and blueprints used to 3-D print satellite, rocket, and defense-related prototypes, the department said.

The Chinese Embassy in Washington did not immediately comment. The three companies could not immediately be reached.

"Outsourcing 3-D printing of space and defense prototypes to China harms U.S. national security," said Assistant Secretary of Commerce for Export Enforcement Matthew Axelrod. "By sending their customers’ technical drawings and blueprints to China, these companies may have saved a few bucks—but they did so at the collective expense of protecting U.S. military technology."

The orders cuts off not only the right to export items but also to receive or participate in exports from the United States or reexports of items subject to the regulations.

Commerce said without customers’ advance consent or knowledge "these drawings were provided to manufacturers in China to 3-D-print the items without the required U.S. Government authorizations."

The information illegally sent to China "included sensitive prototype space and defense technologies."