Pakistan’s police arrested 50 villagers who were part of a mob that burned a Christian couple to death on Tuesday, for allegedly desecrating pages of the Quran. The woman, a mother of three, was pregnant at the time of her death, according to reports.

Shama, 25, and her husband were tortured and burned alive inside the furnace of a brick kiln where they worked as laborers, reports said. According to officials, a religious leader in the region had instigated the public, but his name was not disclosed. Witnesses and police officials told Dawn, a local newspaper, that announcements were made from local mosques urging villagers to gather at the brick kiln, and hundreds responded to the calls. Five police officials reportedly tried unsuccessfully to save the couple from the mob.

“She was screaming that she was unaware of what the papers were about, but no-one listened to her,” Bilqees, a local Muslim resident, said, according to Dawn.

Police officials said that the arrests were made in the eastern town of Kot Radha Kishan near the India-Pakistan border. Local police have also registered a case against 660 villagers and blocked roads leading into the Christian-dominated town of Chak 59, which lies about 2 miles from the location where the incident took place.

"HRCP (The Human Rights Commission of Pakistan) is shocked and saddened beyond words by the callous murder of the couple and their unborn child," the group said, according to CNN, adding that its team "did not come across any evidence of desecration of the Holy Quran."

Under Pakistan’s blasphemy laws, any person who insults Islam or the Prophet Muhammad can be sentenced to death. Last month, a Pakistani court upheld a death sentence awarded to Asia Bibi, a Christian woman charged with blasphemy for allegedly making derogatory remarks about Islam and the Prophet Muhammad.