A teenager is being hailed a hero after rushing into a burning home to save a five-year-old girl from a raging inferno.

Mace Jefferson, 16, was walking past the Northcote Avenue home in Swansea Heads, south of Newcastle, with friends on Thursday afternoon when it went up in flames.

WATCH THE VIDEO ANOVE: Teen hero saves girl from deadly house fire

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Inside the smoke-engulfed home were a grandmother and twin five-year-old girls.

Without a second thought, the young apprentice carpenter rushed towards danger.

“It was just an instinct. I just had to help her in any way I could,” Jefferson said.

He spotted one of the five-year-old girls as the home burned around her.

“It was more just the sight of seeing the little girls standing there,” he said. “I just couldn’t bear to not do anything about that.”

Smashing his way through the window, he pulled her to safety.

“I just wanted to get her out of there,” he said. “It brought a bit of sadness to me. It’s the way that she looked at me.”

But the heroic rescue came at a cost. While trying to save the girl, Jefferson severed several tendons in his leg.

“My Achilles tendon in the back of my leg, there’s three parts of it and I’ve gone through two of them and 70 per cent of the other one,” he said.

His mother Alicia Jefferson said she wasn’t surprised by her son’s actions.

“I know that he would always jump to help someone where he can. He’s quite the empath,” she said.

Despite Jefferson’s heroic efforts, the other five-year-old girl could not be saved and was found dead inside.

An 87-year-old woman suffered burns and was taken to hospital.

The cause of the horrific blaze is still under investigation.

“Our heart goes out to the family and it’s just such a sad time for them as well,” Alicia said.

As one family navigates tragedy, Mace faces a lengthy recovery from his hospital bed.

“I’ve just started an apprenticeship, carpentry, and it’s going to set me back from that for a bit,” he said.