The U.S. Treasury has announced sanctions against 271 employees of the Syrian government agency that the United States believes is responsible for developing chemical weapons like those used in an attack on dozens of civilians in the country earlier this month.

The 271 employees of Syria’s Scientific Studies and Research Center have "expertise in chemistry and related disciplines and/or have worked in support of [the center's] chemical weapons program since at least 2012," the Treasury Department said in a statement. Some of the 271 sanctioned had worked in support of the agency's chemical weapons program for five years or more, the department said.

The April 4 chemical attack in the village of Khan Sheikhoun, Syria, killed more than 80 people. The U.S. afterward launched a missile strike on the air base linked to the attack.

"These sweeping sanctions target the scientific support center for Syrian dictator Bashar al-Assad’s horrific chemical weapons attack on innocent civilian men, women, and children," U.S. Treasury Secretary Steven Mnuchin said.

"The United States is sending a strong message with this action that we will not tolerate the use of chemical weapons by any actor and we intend to hold the [government] regime accountable for its unacceptable behavior," a Treasury Department statement said.

The designation of the 271 Syrians doubles the number of individuals and entities sanctioned by the United States in response to Syria-related executive orders, the Treasury Department statement said.

According to the National Threat Initiative, a thinktank in Washington, The SSRC is based in the Syrian capital Damascus and was founded in 1969. It has had a relationship with the Syrian army since 1973, the organization said.

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