Pakistani authorities are investigating a video that appears to show paramilitary forces shooting to death an unarmed teenage boy in the southern port city of Karachi, officials said Thursday.

Karachi

The video aired repeatedly on TV, sparking another controversy for the Pakistani military, which is still reeling from criticism following the U.S. raid that killed Osama bin Laden last month.

Pakistani security forces are often accused of using excessive force and abusing ordinary citizens.

A spokesman for the paramilitary Rangers claimed its forces detained 18-year-old Afsar Shah because he was attempting to rob people in a park in Karachi on Wednesday. He said a gun was recovered from Shah and he was shot because he was reaching for a Ranger's rifle.

Shah's brother, Salik, a local crime reporter, denied his brother was a robber and accused the Rangers of shooting an innocent person.

"It seems to be a case of routine high-handedness of the Rangers," Salik Shah said. "They misuse their powers by shooting on sight."

The video aired on local television shows a man in civilian clothes holding Afsar Shah by his hair and kicking him toward a group of five Rangers. One Ranger points his rifle at Shah's neck as he appears to plead with them. As Shah moves toward a Ranger with his arms outstretched, he is pushed back and shot and falls to the ground.

Shot in leg and died

It was unclear from the video whether Shah was trying to grab the Ranger's rifle before he was shot or simply pleading for the officers to stop pointing their guns at him.

The Rangers' spokesman said he was shot in the leg and eventually died.

Both the Rangers and the police said Thursday that they will investigate the incident.

Last month, security forces shot and killed a family of five Chechens — a husband, his pregnant wife and their three children — at a checkpoint near the southwestern city of Quetta. Officials initially claimed the five were suicide bombers, but they turned out to be unarmed and video of the shooting further undercut the government's claim. The government has since launched an inquiry into the shootings.

The military is trying to restore its image after the American raid that killed bin Laden in Abbottabad, an army town only about 56 kilometres from the Pakistani capital, Islamabad. Critics have blamed the military for failing to stop the raid and for not knowing that bin Laden was hiding in their midst.