Disturbing police body camera video shows a Virginia woman attacking a Fairfax County police officer with a knife just before he shot her.

Shortly after 10 a.m. on Sept. 16, a 14-year veteran knocked on 33-year-old Sydney Wilson's apartment door to conduct a welfare check in Reston.

When the officer identified himself, Wilson slammed the door, a video shows. The officer knocked again and two minutes later Wilson opened the door and attacked him with a knife.

Wilson allegedly punched the officer in the face several times before the officer drew his gun and retreated down the hallway. The officer fired three times before radio shots rang out and he needed help.

Within minutes, a plainclothes officer was on scene and began CPR.

Chief Kevin Davis said the unnamed officer did what he could to defuse the situation but was unable to retreat further into the hallway when he fired.

“It could have been much, much, much worse,” he said. “The cut and laceration he sustained was at the top of his forehead.”

During welfare checks like these, officers typically respond with a mental health co-responder, Davis said, but the one nearby was on another call.

Davis said he was grateful for that because the co-respondent could also have been seriously injured.

“Every time doctors get out of a police car and walk with a police officer to a door, to an accident scene or to an outdoor scenario, they are exposing themselves to some danger and there is some risk associated with that. ”

Davis said he wasn't sure a co-respondent could have made a difference in this case.

The officer remains on administrative duty during the ongoing investigation.

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