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DESOTO (CBSDFW.COM) – Police from Desoto shot and killed a Dallas man who was suspected of murdering two people in Portland and critically injuring a third individual. A woman who was at a nearby fast food restaurant was also shot, but authorities are not saying who shot her.

Colby Robinson was spotted Tuesday night at a 7-Eleven convenience store located at the corner of Interstate-35E and Wintergreen Road in DeSoto. An alert clerk noticed the suspect after being shown his picture by police just a short time before.

“In my mind, I’m thinking something may happen,” said clerk Brian Watson. “I’m kind of prepared for the worst, but I prayed for the best.”

26-year-old Colby Robinson (source: Portland Police)

Colby Robinson (credit: Portland Police Department)

The clerk stated that he kept his cool while Robinson was in the store, followed him outside and wrote down the license plate number for the U-Haul that he was driving. Another clerk called it into police. “When I seen him, I was like, what can I do? So, I did what I thought was best. I got in my car and got a license plate,” said Watson. “He came in the wrong 7-Eleven. We’re about doing right.”

“Just trying to help before he killed someone else,” Watson continued. “Could have been my brother. Could have been anybody else’s brother. Just get him off the streets.”

Authorities found the truck and started chasing the 26-year-old suspect, who ultimately ditched the vehicle and began to flee on foot. Surveillance video from an Exxon gas station shows the truck come to a stop and Robinson jump out to start running.

Someone inside of the U-Haul truck then shuts the open passenger door and drives away after police speed through the gas station’s parking lot. It is not yet clear who was driving the truck.

The police chase ended in the 6900 block of Altaire Avenue, in the Red Bird area of Dallas, where officers fired shots at the suspect. Robinson was pronounced dead at the scene. There were two officers involved in the shooting. It is not yet known if Robinson fired any shots.

Neighbors reporting hearing a single shot followed by several other shots. One witness said that police were very clear with their demands. “It was a combination of ‘put the gun down’ and ‘put your hands up,'” Isaiah Moreland said. “They were trying to tell him — I guess he had a gun in one hand — they wanted him to put both hands up.”

A woman was also shot at a nearby Jack in the Box as she waited in the location’s drive-thru line. She was taken to the hospital and is expected to be okay. It is not yet known who fired the shot that struck this individual.

(L-R), Andrew Pham, Susie Pham (holding infant daughter) and Gary Pham. (courtesy: Pham family)

Andrew Pham, Susie Pham (holding infant daughter) and Gary Pham. (courtesy: Pham family)

Authorities in Portland said that Robinson killed 33-year-old Gary Pham and 41-year-old Susie Pham in their home on Friday evening, as well as critically injuring 35-year-old Andrew Pham. Police found a 13-week-old baby girl unharmed in the home. She has been placed in the care of her grandparents.

Portland detectives explained that all three shooting victims were involved in the medical marijuana industry, but have not determined if this played a role in the shootings.

Gwendolyn Dixon is Robinson’s aunt, and is heartbroken by the entire situation. “He’s a good kid,” Dixon said. “I don’t think he should have been shot down the way he was by the police.”

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