EMBED >More News Videos WARNING -- GRAPHIC. Surveillance footage shows an alleged use of excessive force on a METRO platform. (No sound)

HARRIS COUNTY (KTRK) -- A former METRO police officer has been indicted by a Harris County grand jury and charged with assault.Officer Jarius Warren is accused of striking Darrell Giles earlier this month while he was sleeping at the Burnett Train Station . The indictment handed down alleges that Warren struck Giles with a baton, causing bodily injury.Giles was initially charged with criminal trespass and resisting arrest. Those charges were dismissed."The video is very disturbing," Harris County District Attorney Devon Anderson said in a statement. "When we have compelling evidence such as this, we immediately initiate an investigation. The case was presented to a diverse grand jury and we wholeheartedly support their decision. This officer used excessive force and should not be wearing a badge."The grand jury found that there was not enough evidence to charge officer D. Reynoso.Giles spoke exclusively to Eyewitness News about what happened during the incident. He says he did nothing wrong."I thought he (Warren) pulled a gun out," he said. "He hit me so hard, he knocked me to the ground, so the first couple licks, he's just standing over me going bom bom bom making some noise."Warren resigned from the Metro Police Department on Monday while under an internal affairs investigation.If convicted, he could face up to a year in jail and a fine of up to $4,000.