A group of US lawmakers has asked the Treasury Department and the State Department to sanction four businesses, including the Israeli spyware firm NSO Group and the UAE cybersecurity firm DarkMatter, for allegedly assisting authoritarian governments in human rights violations.

The MPs seek for punishment against top executives at NSO, DarkMatter, and European internet bulk surveillance businesses Nexa Technologies and Trovicor in a letter delivered late Tuesday and reviewed by the Reuters news agency.

The congressmen requested sanctions under the Global Magnitsky Act, which permits the US to punish people suspected of supporting human rights abuses by freezing their bank accounts and prohibiting them from entering the country.

DarkMatter was unavailable for comment. The other three firms did not respond to Reuters’ calls for comment right away.

The letter also noted a recent Reuters piece last month exposing that NSO malware was deployed against State Department employees in Uganda, which was signed by Senate Finance Committee Chairman Ron Wyden, House Intelligence Committee Chairman Adam Schiff, and 16 other Democratic senators.

According to the lawmakers, the spyware sector is reliant on US investment and banks.

“The US government should apply financial sanctions to properly punish them and send a clear signal to the surveillance technology industry,” they said.

The corporations, according to the letter, aided in the “disappearance, torture, and murder of human rights activists and journalists.”

As a result of a flood of media revelations linking surveillance businesses to human rights abuses, Washington has increased its monitoring of them.

“These surveillance mercenaries marketed their services to authoritarian countries with a lengthy history of human rights violations, providing tyrants with massive spying powers,” Wyden told Reuters. “As one might expect, those countries exploited surveillance capabilities to imprison, torture, and murder journalists and human rights activists. The Biden administration has the opportunity to cut off the flow of American funds and put these companies out of business for good.”

NSO was placed on the so-called Entity List by the Commerce Department in November, barring US suppliers from providing software or services to the Israeli spyware company without special clearance.