Suffolk County Police Homicide Squad and Arson Section detectives are investigating a fire that killed an East Setauket woman and injured a man and infant in the early morning hours of Feb. 18.

Sixth Precinct officers responded to the home, located on Old Town Road, after a 911 caller reported a fire at the location at 12:01 a.m. Stephen Ortner, a resident of the home, was able to escape through a second-floor window onto a roof ledge and hand his 10-month-old son to a passerby below, who then handed the child to rescuers. Ortner was then able to climb down to the ground, according to SCPD.

According to Dave Sterne, the Setauket Fire District’s manager, Ortner tried to get back inside to help the child’s mother, Lisa Ostrowski. However, when department Chief Richard Leute arrived on the scene and saw him, he advised the father not to do so as the house was engulfed in flames. Ortner then jumped and Leute caught him.

Ostrowski, 31, the mother of the child, was not able to escape the home and was found dead once the fire was extinguished. Stephen Ortner, 30, and his son Leo Ortner were transported to Stony Brook University Hospital, where the father was treated for serious injuries and his child for non-life-threatening injuries.

There were no other occupants of the home and no other injuries were reported.

A preliminary investigation has determined the cause of the fire to be non-criminal in nature.

Ortner and Ostrowski’s aunt Barbara Iannuzzi-Prass set up a GoFundMe page, Tragic Fire support for Lisa, Baby Leo and Steven. As of Feb. 19, more than $42,000 was raised from nearly 600 people.

Ianuzzi-Prass wrote on the page that Ortner and Ostrowski were engaged. She reported that both Ortner and his son were in the ICU with severe burns and in critical but stable condition.

“Lisa will need a proper funeral and Steven and Leo will need to restart their lives once they are out of the hospital,” Ianuzzi-Prass wrote.