The main suspects in the murder of a Christian couple, thrown into a fire by a mob for alleged blasphemy, have been bailed, according to reports.

Shahzad Masih and Shama Bibi were murdered in November 2014. Yousaf Gujjar and three others had been charged for their deaths, accused of inciting a crowd to beat and torture the couple and then throw them into a burning brick kiln. It is not clear whether the couple were already dead. They had three children, and Shama was pregnant.

"This reluctant attitude of the police suggests complicity and does not help do justice," said Christian lawyer Mustaq Gill, according to the Fides News Service, which is an agency of the Vatican.

At the time the Christian couple were said to have 'desecrated the Quran'. However they were indentured labourers at the kiln, and one of those charged is the owner, so there may have been financial motivations for inciting the crowd.

Brick kiln labourers are subjected to harsh working practices, with the Bonded Labour Liberation Front Pakistan estimating that 4.5 million are indentured labourers with no freedom of movement. They are paid as little as £1.30 a day and child labour is common: according to ActionAid, up to 1.7million children from the age of five are working in illegal brick factories for up to 14 hours a day.

Blasphemy is a sensitive issue in Pakistan, with allegations often prompting mob violence.

Hundreds of people were involved in the incident, and more than 100 charged.