Liam Payne has been hailed a hero for helping to save a friend when a horrific fire broke out at the One Direction star's London apartment by beating out the flames.

Payne's childhood pal Andy Samuel was left with 20 per cent burns to his chest, legs and arms after a heater on the balcony of the singer's penthouse exploded at a barbecue on Monday (02Sep13).

At the time of the accident, Payne was in the kitchen but he rushed out to extinguish the flames and douse his pal with water.

Now Samuel's stepfather Matthew Baker has praised the pop star for his heroic actions, telling Britain's Daily Mirror, "We are so grateful to Liam because he saved his life. The lantern just exploded as Andy was lighting it and it took the full force of the flames. Liam helped him by beating out the flames and dousing him with water. He acted quickly and swiftly.

"What happened was absolutely awful. My son is very poorly. I've spoken to Liam on the phone and he told me exactly what happened. He is very shocked himself. It's bad enough but it could have been a lot worse."

Andy's 12-year-old sister Harriet also posted a tweet to Payne, writing, "I want to thank Liam for saving my brother."

Samuel remains in a stable condition with Payne at his bedside, while two other unnamed victims were also taken to the hospital to be treated for superficial burns to their hands.

Officials are currently investigating the cause of the fire.