A man was stoned to death after being accused of blasphemy in northwest Nigeria, authorities and activists said, sparking outrage on Monday, June 26 from rights groups worried about what they said were growing threats to religious freedom in the region.

According to VOA news, Usman Buda, a butcher, was killed Sunday in Sokoto state’s Gwandu district after he "allegedly blasphemed the Holy Prophet Muhammad” during an argument with another trader in a marketplace, police spokesman Ahmad Rufa’i said in a statement Sunday night.

Residents shared videos that appeared to be from the scene showing a large crowd that included children pelting stones at Buda on the floor as they cursed him.

Rufa'i said a police team was deployed in the area but when they arrived, "the mob escaped the scene and left the victim unconscious." He was later declared dead at Usmanu Danfodiyo Teaching Hospital in Sokoto, Rufa'i said.

The killing was the latest attack rights campaigners have said threatens religious freedom in Nigeria’s predominantly Muslim northern region. Blasphemy carries the death penalty under Islamic law in the area.

Amnesty International Nigeria’s office said the failure to ensure justice in such cases would encourage more extrajudicial killings. "The government is not taking the matter seriously and that has to change,” Isa Sanusi, acting director of Amnesty International Nigeria, said.