Beirut, London – While Syrian regime forces appeared on Monday to be racing with experts from the Organization for the Prohibition of Chemical Weapons (OPCW) to Khan Sheikhoun to hide the remaining proof of their chemical attack on the town early this month, Washington enforced sanctions against dozens of employees at Syria’s Scientific Studies and Research Center.

In anticipation of the expected attack by regime forces against the opposition-controlled Khan Sheikhoun, regime warplanes pounded on Monday the popular market in the center of the town, killing five civilians, including one child, and injuring several others, the Syrian Observatory for Human Rights said.

The Observatory added that the number of casualties was expected to rise due to the critical condition of several of the wounded.

An activist in the city of Khan Sheikhoun was quoted by the “Office of Syria News” as saying that civil defense workers removed the bodies of civilians and transported the injured to the nearest hospitals, due to the absence of any medical center in the city.

In Hama, the Observatory said regime forces made advances by capturing the village of Buwayda and the Zaleen checkpoint, hours after controlling the town of Masasina.

Meanwhile, the US Treasury Department ordered on Monday sanctions against 271 employees of Syria’s Scientific Studies and Research Center, the regime agency responsible for developing and producing non-conventional weapons. The Treasury Department prohibited any US individual or company from dealing with those employees.

Treasury Secretary Steve Mnuchin told reporters at the White House: “The United States is sending a strong message with this action that we will hold the entire (Bashar) Assad regime accountable for these blatant human rights violations in order to deter the spread of these types of barbaric chemical weapons.”