EXCLUSIVE: Inmate mistakenly allowed to walk out of Harris County jail

HARRIS COUNTY (KTRK) -- An internal affairs investigation is underway into how a Harris County inmate was able to walk out the door instead of being processed into jail.

William Montgomery, 48, also known as Willie Boone, remains free after walking out of the Inmate Processing Center on Commerce late Thursday night. He had just been brought in from Auburn, California by a private transport service called PTS of America. Montgomery, who has an outstanding credit card abuse case in Harris County, was let out of the vehicle and uncuffed.

Sources tell Eyewitness News a deputy -- apparently mistaking Montgomery for someone loitering -- opened the door and told him to get out. The exchange was captured by a jail security camera.

"This whole situation has triggered an internal affairs investigation," Ryan Sullivan, a spokesman with the Harris County Sheriff's Office confirmed.

He called what happened an "erroneous release."

"The investigation will reveal where the breakdown was and who was responsible, added Sullivan.

"We already signed over the inmate and he was in their (HCSO) custody at the time," said Frank Caruso, Director of PTS of America, denying any responsibility.

Montgomery has a criminal record of non-violent offenses including theft and drug possession.

He is considered an escapee. When caught, he will face additional charges, said Sullivan.