Police in eastern Pakistan have detained scores of people accused of torching the homes of more than 100 Christians after hearing reports that a Christian had made derogatory remarks to his Muslim friend about the Prophet Muhammad.

Thousands of Muslims on Saturday rampaged through Joseph Colony, a Christian area of Lahore, to protest the alleged blasphemous remarks. Hundreds of Christian families fearing for their safety fled the area.

On Sunday, Christian demonstrators protested across a main highway in Lahore to demand that the government rebuild the destroyed homes.

The Christian man, Sawan Masih, is in police custody, facing possible charges of blasphemy.

Muslim-majority Pakistan has some of the world's toughest penalties against blasphemy. Anyone found guilty of insulting Islam and the Prophet Muhammad faces the death penalty.