The shootout Monday on an Alabama interstate that killed a teenage girl and wounded a 9-year-old boy who were caught in the crossfire is believed to be gang-related, authorities said.

Mobile County Sheriff Paul Burch said the reason investigators believe gangs were involved is because the shots that struck the two victims on I-165 in Prichard were intended for the boy’s 18-year-old brother, according to WKRG.

The 15-year-old girl who died was a cousin to the 9-year-old and 18-year-old.

A sheriff’s office spokeswoman said the incident it was the second time the boy was shot by a gunman who was pursing someone else.

All three were inside the SUV seated in the middle row. In the backseat was a 4-year-old child who Burch described as the sibling of the 15-year-old who was killed. The 4-year-old was not harmed, the sheriff said.

Burch said his agency has not identified the shooter.

He said the mother of the intended victim “is being less than cooperative with us, and I find that very alarming.”

The Sheriff’s Department has not yet released the name of the 15-year-old victim.

The agency is asking the public, if they have any information about the shootout, to contact them at 251-574-8633 or to leave information on their online Crime Tip form.