The dead, including a seven-year-old girl and her baby sister, were Ahmadis, who consider themselves Muslim but believe in a prophet after Mohammed. A 1984 Pakistani law declared them non-Muslims and many Pakistanis consider them heretics.
Police said the late Sunday violence in the town of Gujranwala, 220 km (140 miles) southeast of the capital, Islamabad, started with an altercation between young men, one of whom was an Ahmadi accused of posting “objectionable material”.
“Later, a crowd of 150 people came to the police station demanding the registration of a blasphemy case against the accused,” said one police officer who declined to be identified.
“As police were negotiating with the crowd, another mob attacked and started burning the houses of Ahmadis.”
The youth accused of making the Facebook post had not been injured, he said.