A 15-year-old boy who was set on fire in Lahore, Pakistan on Friday, allegedly because he said he was a Christian, has died in hospital.

Before he died Nauman Masih told police that two men had approached him and asked him about his religion. When he said he was a Christian, they beat him, and when he tried to run away they followed him, threw kerosene over him and set him on fire, Mehwish Bhatti, Pakistan officer for the British Pakistani Christian Association, told Christian Today on Monday.

Doctors said at the weekend that 55 per cent of his body was burnt, but expected him to make a good recovery.

However yesterday he was taken for plastic surgery and afterwards told that he had a 50 per cent chance of survival, Bhatti said this afternoon. He died in the early hours of Wednesday morning.

Nauman's father died when he was young, and his mother remarried. His uncle and aunt took him into their care, and Nauman referred to them as his parents.

His uncle, Nadeem Masih, told Bhatti that Nauman was "just like his son" and it was very hard to lose him. Bhatti said he was crying as he spoke on the phone.

The attackers were masked when the incident took place, making it unlikely that they will be caught.

Nadeem said that the authorities have shown little interest in pursuing the case, but Bhatti told Christian today that he will go to the police.

"He said it was not easy to forgive them, he wants justice," Bhatti said.

The young man was training to be a tailor, and was on his way to the tailor's shop when the attack took place.

The attackers started insulting his mother and sister, and Nauman fought back in defence, before the kerosene was poured over him. He put out the flames by rolling in the sand on the ground.

Nauman reportedly said: "I was running when a heap of sand came my way, I lay down on the sand, and a few people from the community put out the fire by putting sand on me. I became unconscious, and they called the emergency medical helpline and called [for] an ambulance."

He was treated at Mayo Hospital in Lahore, where a senior political health advisor visited him. Adviser to Minister of Health Khwaja Salman Rafique told the medical team to give the boy the best possible care, the Express Tribune reported.

Nauman said the men didn't give any reason why they were stopping him. According to Bhatti the boy said before he died that he didn't have "any enmity with anybody" and didn't know why someone would do this.

There were conflicting reports about who might be responsible. The investigating officer told the Express Tribune that the boy's grandfather had blamed Nauman's uncle for planning the attack.

"We have recorded the statement of Nauman's grandfather. He has accused Nauman's uncle, Nadeem, and his wife, for ordering the attack. He said the couple wants to kill Nauman to get his three-marla house. Nauman's father had passed away three months ago," the officer said.

The incident comes less than a month after suicide bombings by the Pakistani Taliban at two churches in Lahore left 14 people dead and 78 wounded. This attack led to widespread protests in the region calling for better protection for Pakistan's Christians.