GARLAND (CBSDFW.COM)— Police in Garland have been working around the clock to track down the gunman responsible for a weekend triple murder in the city.

The deadly shooting happened aroud 7:30 Sunday night at a Texaco convenience store in the 700 block of Walnut Street.

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(credit: CBSDFW.COM)

Two of the victims have been identified as Xavier Gonzalez, 14, and Ivan Noyola, 15.

Investigators say a white pickup truck pulled up to the store and a man with a gun stepped out of the passenger side and began firing. After the shooting the gunman and the driver sped away from the scene.

Three men, whose identities have not been released, were pronounced dead at the scene and another male victim was taken to a nearby hospital in critical condition.

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Police have not said what the motive behind the attack might have been, but do believe one of the victims may have been an employee of the store.

The fatal shooting comes as a shock in what is normally a safe neighborhood. “Nothing to this magnitude has occurred here, so this is a shocker to us… especially being so close to downtown Garland,” said Garland PD Public Information Officer Lt. Pedro Barineau. “Anytime a person’s life is taken it’s alarming for us, it’s a tragedy. We’re gonna do everything we can to find out who did this, so we can get them off the streets.”

Barineau said the shooting does not appear to be related to a robbery and that investigators are not yet sure whether the shooter knew the victims. Officials did confirm that no weapons were found on any of the victims.

The suspected gunman remained at large Monday morning. Police believe he fled in a 4-door, white, Dodge pickup.

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Anyone with information is being asked to call the Garland Police Department at 972-485-4840. Tipsters can remain anonymous by calling Garland Crime Stoppers at 972-272-8477 (TIPS). A reward of up to $5,000 is being offered for information that leads to the identity and arrest of the suspect. Staff