DALLAS (CBSDFW.COM) – Police in Dallas are on the lookout for two men who shot a girl and her teenage brother after a group of teens set out to make a sale from a classified ad website.

The shooting happened after midnight in the Rochester Park neighborhood, just east of Interstate-45.

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(credit: CBSDFW.COM)

Police say the 12-year-old girl and her 15-year-old brother were riding along with their older brother and his girlfriend, who had placed an add on Craigslist to sell a cell phone and arraigned a meeting with a buyer.

The sale didn’t go as planned, because the buyer never showed up. But the couple said they were flagged down by two men they didn’t know. Feeling “unsafe” the older brother began to drive away and that’s when the suspects opened fire.

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The younger siblings, who were in the back seat of a car, were hit by bullets. Their brother was able to drive to Lamar Street and call for help. The young girl was rushed to Children’s Medical Center — her exact injuries aren’t known but officials say she is in critical condition. Her 15-year-old brother was grazed by a bullet and was treated at Baylor Medical Center and released.

Detectives are appealing to those who live in the area, believing someone can lead police to the suspects.

“Somebody out there where the shooting took place… the community knows each other well. These [kids] talk a lot, so I’d encourage the parents of these children… if they hear something, say something,” said Dallas Deputy Police Chief Thomas Castro.

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Dallas Police Chief Renee Hall tweeted her prayers to the teen victims of the shooting.