The suspect accused of ambushing two National Guard members outside a metro station in downtown Washington, D.C., was shot by another Guard member, multiple sources familiar with the investigation told CBS News.

The two Guard members who were wounded were posted outside a metro station when a gunman opened fire without warning in what law enforcement sources described as a “clear ambush” and “calculated attack.”

The first victim — a female Guard member — was struck immediately and collapsed where she stood, the sources said. She sustained at least two gunshot wounds during the ambush. 

The suspect, who was wielding a handgun, had four rounds in his firearm initially, sources said. After he fired them, he then took the fallen Guardswoman’s weapon and used it to continue shooting, striking the second Guard member, the sources said. 

A third Guardsman stabbed the suspect with a pocketknife, while a fourth returned fire and shot the suspect multiple times, ending the attack.

The wounded Guard members were deputized for the deployment but were not operating as law enforcement and did not have arrest powers, the sources said. They were stationed outside the metro stop as part of a high-visibility foot patrol that consisted of presence-based security, not active policing, the sources explained.

By Nicole Sganga and Jennifer Jacobs