A brother and sister have both died after a devastating house fire in Cortlandt Manor.

They've been identified by officials as 15-year-old Jeremiah Toone and 17-year-old Alina Toone.

Crews were called to a home on Sherwood Road around 2:30 a.m. Wednesday for a structure fire with people trapped inside.

Firefighters arrived to find flames venting from the front of the home, making entry through the front door impossible.

With reports of children inside, crews raised ladders and entered through second-floor windows to reach victims.

Two teenagers were pulled from the home pulseless, and CPR was started immediately at the scene.

"Two teenagers… came out in serious condition with CPR being administered immediately," said Fire Chief Thomas Eade.

Officials say both suffered severe burns covering about 40 to 50% of their bodies.

Authorities say the siblings later died at hospitals.

Two other people, believed to be the teens' mother and another sibling, were also taken to the hospital with minor injuries.

The family dog died in the fire.

Firefighters say the rescue effort was especially challenging, as crews had to perform lifesaving care while also battling the flames.

"You have to focus on patient care… with cardiac arrest… while still trying to have the firefight in the background," Eade said.

A firefighter was also treated for exhaustion following the intense response.

Officials praised the crews' actions, calling them heroic under extremely dangerous conditions.

The cause of the fire is believed to be electrical but remains under investigation.

Jeremiah and Alina were students at Putnam Valley High School.