The Chargers are investigating video of a security guard on the sideline during Sunday's game. USATSI

The San Diego Chargers are investigating a disturbing video of a security guard on the sidelines at Qualcomm Stadium during Sunday's game against the Oakland Raiders.

A video, first reported by ABC 10 in San Diego, shows an employee from Elite Security who was working at the Chargers game and stationed near the end zone. In the video, the security guard appears to be performing a sexual act while standing along the sideline near a group of cheerleaders and a photographer. The man is wearing a ballcap, red jacket, black pants and standing several feet away from cheerleaders performing on the sideline.

The now-viral video is posted on ABC 10's site and other sites, but is obviously not suitable for all audiences.

"We are aware of the disturbing actions of an Elite security staff member at Sunday's game," Chargers director of security Bill Stetson said in a statement. "We apologize to any fans who may have witnessed the incident. Elite Security is currently investigating the incident and has vowed to take immediate and appropriate action."

The Chargers also issued a statement from Elite Security.

"Elite has become aware of the social media post of inappropriate actions of an Elite staff member at Qualcomm Stadium on December 18th," the statement reads. "Elite has employed thousands of people over the past 21 years, insists on the highest moral standards from our employees and regrets this isolated incident. Elite is currently investigating the incident and has no additional comment at this time."