KHAR, Pakistan — A gang of Pakistani militants executed two Afghan prisoners in front of thousands of cheering supporters Friday, beheading one man and shooting the other after accusing them of aiding a U.S. missile strike.

The executions in the Bajur region highlighted the power of local Taliban forces in lawless tribal areas near the Afghan border.

Also Friday, a top U.N. official expressed fears that Pakistan’s peace deals with militants were sparking a wave of similar abuses.

Militants calling from the loudspeakers of mosques summoned people to the banks of a stream outside the town of Khar, about 120 miles northwest of Islamabad. At least 5,000 people gathered to watch the executions.

Masked militants pulled the two blindfolded Afghans from a car and forced them to kneel on the ground.

Waliur Rehman, a local Taliban commander, told the crowd that the two men had confessed to aiding in the strike on a house in the border town of Damadola that killed 14 people last month. The men disclosed the names of others accused of involvement, who would be killed as well, Rehman said. Pakistan’s army lodged a formal protest to “allied forces” in Afghanistan after saying Pakistan had concluded the attack was launched by drones from across the border. The U.S. did not comment on the incident.

“Whoever, for the sake of money, for the sake of America, harms the interest of the Islamic world will meet the same fate,” Rehman said.

Gunmen with daggers then pounced on one of the men — identified as Jan Wali, 36 — decapitated him and waved his bloody head to the cheering crowd, according to an Associated Press reporter and AP Television News footage from the scene.