Pay Close Attention to What Happens in the Upper Left. Police Say It Holds the Key to Another St. Louis Shooting.

The picture is grainy and hard to make out, but police say it vindicates their position and shows the reason 18-year-old Antonio Martin was shot Tuesday night: He pointed a gun at a police officer.

Image via YouTube

Surveillance video posted to YouTube Wednesday morning by St. Louis County Police shows the scene where Martin was shot by a police officer.

Near the end of the video, a figure can be seen holding what could be a gun and pointing it at the police officer.

Watch below:

Here's the police statement accompanying the video:

Surveillance video from officer-involved shooting in Berkeley, Missouri. This video shows the suspect pointing a gun at the officer.

More information on the incident:

At approximately 11:15 PM on December 23, 2014, a police officer with the City of Berkeley was conducting a routine business check at the Mobile Gas Station located at 6800 N. Hanley when he observed two male subjects on the side of the building. The Berkeley Police Officer exited his vehicle and approached the subjects when one of the men pulled a handgun and pointed it at the officer. Fearing for his life, the Berkeley Officer fired several shots, striking the subject, fatally wounding him. The second subject fled the scene. The Berkeley Police Department requested the St. Louis County Police Department's Crimes Against Persons Unit to handle the investigation. St. Louis County Police Detectives have recovered the deceased subject's handgun at the scene. At this time, I cannot confirm the identity of the deceased subject. The investigation is on-going and further details will follow as they become available.

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