News4 has learned police are investigating an assault aboard a Metro train last weekend during which an adult elbowed a teen in the face.
A witness of the assault told News4's Jackie Bensen he was riding the Orange Line between Clarendon and East Falls Church Metro stations late Friday night, when he saw an altercation between two people growing more intense.
"I couldn't believe it was happening," he said. "I felt helpless about it. I was wearing a back brace."
Another passenger shot cell phone video of the assault, which shows the older man using his elbow to repeatedly punch the other person, who appeared to be a young teen, in the face. The witness said he assumed they were related.
"Apparently the son said something that the father thought was disrespectful," he said. "And then you can see on the video what ensued. It was really pretty shocking."
He said riders urged the older man to calm down, and he stopped. The teen appeared to have a bloody nose and a swollen face.
The witness got off the train at the next station and is still disturbed by what he saw that night.
"I just had a hard time sleeping the next couple nights, thinking about it," he said.
The witness said he contacted police. A spokesperson for Metro said Metro Transit Police detectives are reviewing the cell phone video.