An Afghan national is being investigated as a possible terrorist suspect in the shooting of two West Virginia National Guard members, leaving one dead and another injured, as the Trump administration ramped up its crackdown on illegal immigration.

In a late-night Thursday Truth Social post, President Donald Trump wrote "this refugee burden is the leading cause of social dysfunction in America....I will permanently pause migration from all Third World Countries to allow the U.S. system to fully recover."

President Trump also announced Thursday that U.S. Army Specialist Sarah Beckstrom, 20, had died from her injuries in Wednesday’s shooting in the nation's capital. U.S. Air Force Staff Sgt. Andrew Wolfe, 24, was "fighting for his life" and remained hospitalized in critical condition, the president said.

"I want to express the anguish and the horror of our entire nation at the terrorist attack yesterday in our nation's capital, in which a savage monster gunned down two service members in the West Virginia National Guard, who were deployed as part of the DC Task Force," Trump said in a Thanksgiving call with service members.

The suspect, identified as 29-year-old Rahmanullah Lakanwal, was shot moments after the attack and was hospitalized in serious condition. The motive behind the deadly shooting is currently unknown.