A woman found out her south Alabama home was on fire and ran home to rescue one child from the burning structure, but two other children were killed, authorities said.

The woman, whose name was not released immediately, was next door to her own mobile home when she was alerted to the fact the structure was on fire Thursday night, Sgt. Mark Bailey of the Mobile County Sheriff’s Office told WALA-TV.

The woman was able to save a 10-month-old boy from his crib. But a 4-year-old and a 2-year-old, both boys, were pronounced dead at Providence Hospital, authorities said.

The mother sustained burns and was being treated for her injuries. It was not clear why she’d gone next door or whether anyone other than the three children were home when the fire occurred.

A photo showed what appeared to be soot above a window of the mobile home, and investigators believe the fire started in a front bedroom, authorities said, but the cause of the blaze was under investigation.