A Dallas man who recorded the apparent point blank murder of a police officer spoke with NBC 5 overnight Friday, recalling what he witnessed.

The man, identified as Jason Young, said he was waiting for a bus when he saw people running after gunshots were heard downtown Thursday.

Young told NBC 5 he saw an officer hiding behind a pillar and, soon after, a second person run up behind him in body armor and gear.

The man said he thought it was another police officer until the man shot the officer at point blank range.

"I'm still in shock. I mean, I've never seen anything like that before in my life. Never would have expected that," Young said. "We all just hit the ground, just laid on the ground for a few minutes."

Though the video showing the officer's shooting has been placed on social media, NBC 5 has decided to not share the video.

After shooting the officer, Young said the man then ran around the north side of El Centro College where he shot out the windows and entered the building.

Five officers were killed, including four Dallas police officers and one DART police officer, in the ambush attack. Officials have not said which officer was shot in the video.

Shortly before 3 a.m., Dallas police said a standoff at the school was over after the suspected shooter had been "neutralized."

NBC 5's Chris Van Horne contributed to this report.