ARLINGTON, Texas (CBSDFW.COM) – Arlington Police Chief Will Johnson called the deadly shooting of 30-year-old Margarita “Maggie” Brooks Thursday evening “an absolute tragedy” and extended condolences to the Brooks family and everyone impacted by what happened.

Maggie Brooks (Facebook)

Brooks was reported passed out in a grassy area behind a business, when an officer came to check on her.  He ended up accidentally shooting and killing her.

“Our hearts are broken,” said Chief Johnson.

Arlington Police Chief Will Johnson (CBS 11)

A 25-year-old Arlington Police officer, who graduated from the police academy in February, shot and killed Brooks at Cantor and Collins in North Arlington around 5:30 p.m. Thursday.

Chief Johnson said the officer called out to the woman to ask if she was okay and asked if it was her dog.  The dog moved toward the officer barking.

The officer fired three shots at the dog, but the woman was struck.

Arlington Police released the body cam video showing this:

Brooks suffered a fatal wound to the chest, according to the Tarrant County Medical Examiner’s Office.  Her cause of death was ruled a homicide by the Medical Examiner.

She was never the intended target of the officer’s use of force, Chief Johnson said.

The Arlington Police Department has now launched two investigations – a criminal to determine if the officer broke the law – and an administrative one to see if he followed department standards and training.

Arlington officer-involved shooting (CBS 11)

The officer has not been identified, but the chief told us he had just been released from field training July 1- and had undergone training to deal with dogs in the field as recently as February.

The officer has been placed on routine administrative leave.

WATCH CHIEF WILL JOHNSON’S NEWS CONFERENCE HERE:

The dog, a lab mix, weighs 40 pounds.  It was injured and is currently in quarantine at the Arlington Animal Shelter.

The incident was captured by body camera which will be included in the investigation.