Three young siblings riding in the back seat of their mother's car were shot early Wednesday morning, about 90 minutes after police responded to another shooting at the same apartment complex.

A 10-year-old boy and his 4-year-old sister were in stable condition Wednesday morning at Children's Medical Center of Dallas, police spokesman Cpl. Gerardo Monreal said. Their 12-year-old sister was in critical condition at the same hospital, although her injuries were not considered life-threatening, Monreal said.

The shooting happened around 1:30 a.m. Wednesday. The three injured children were among five siblings riding in the back seat of their mother's four-door Mercedes sedan. The mother was behind the wheel with an adult daughter riding in the passenger seat, police said.

Another relative was following them in a separate car when the shooter began firing into the passenger side of the Mercedes, hitting three of the children. The mother transferred the three injured children to the relative's car, and that relative drove to the hospital, police said.

Police don't know whether the shooter was in another vehicle or approached on foot. It is also unclear why the family was leaving their apartment complex at such a late hour, Monreal said. Police have not made any arrests and are not identifying the shooting victims or their family members.

"Detectives are still interviewing witnesses and talking to people of interest," Monreal said.

Police responded to an earlier shooting of an elderly woman at the apartment complex. Police said the woman was hit by a stray pellet from a shotgun blast around 11:50 p.m. Tuesday. She complained of chest pains and went to a hospital but was uninjured, police said.

Police don't yet know if the shootings are related.

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