A Texas woman was found fatally shot in the back after an armed man called 911 from a nearby gas station, saying he’d opened fire on his wife in self-defense, officials told news outlets.

Deputies responded to an apartment complex on San Antonio’s east side at about 8:30 a.m. Tuesday, July 2, the Bexar County Sheriff’s Office told WOAI. They arrived to find the apartment door open and a woman lying face down inside, with gunshot wounds to her back, the sheriff’s office said.

She was taken to a hospital where she died, officials told the station. The sheriff’s office didn’t publicly identify the woman but said she was in her 30s.

Elsewhere in the apartment, deputies said a 6-month-old boy was sleeping and unharmed by what happened, KSAT reported.

The man, who officials also haven’t identified, told deputies he shot the woman to protect himself. However, the sheriff’s office said he will likely be charged with murder, according to the station.

Though authorities have not confirmed whether the man and woman were in a relationship, they are investigating the killing as a domestic violence incident, KENS reported.

Officials told the station the baby has been placed with family.