Several gunmen opened fire on Pakistani troops stationed at the military installation in Gujrat, to the southeast of capital city Islamabad on early Monday morning.
The attack occurred after members of Difah-e-Pakistan, or Defence of Pakistan, movement wrapped up a rally inside Gujrat protesting the country's decision to allow American and NATO troops to move weapons and equipment through the country into Afghanistan.
Basharat Mahmood, Gujrat's police chief, said the protestors had spent the night inside the army base before Monday's protest inside the city. He suspected the gunmen may have used the group as cover for the attack.
“It is surely a terrorist attack,” Mahmood told the AP. “The attackers could have taken cover. They could have hid themselves among the protesters.”
Difah-e-Pakistan is reported to have strong ties to Pakistan's Inter-Services Intelligence directorate, and counts the founding fathers of the Taliban and the terror group Lashkar-e-Taiba among their senior leaders, the AP reports.
Lashkar-e-Taiba has been accused of orchestrating the deadly Mumbai terrorist attacks in November 2008 and Afghan and Pakistani factions of the Taliban have been conducting terror attacks against U.S, coalition and government forces in both countries since 2001.
Pakistani officials also reportedly used the group to ramp up the pressure on American officials during the contentious negotiations to open up Pakistani supply lines to coalition forces in Afghanistan.
Last Thursday, Islamabad opted to allow U.S. and NATO forces to move materiel through the country.
The decision followed Secretary of State Hillary ClintonHillary Rodham ClintonConquering Trump returns to conservative summit How the candidates for DNC chair stack up ahead of Saturday's vote DNI official challenges reports of low morale in intelligence community MORE's unexpected apology for last November's errant U.S. airstrike that killed 24 Pakistani soldiers and prompted the shutdown of the routes.
While the White House and the Pentagon have repeatedly expressed their regret for the air raid, no one from the Obama administration had formally or informally apologized for the attack until last week.
Defense hawk Sen. John McCainJohn McCainWhy the GOP cannot sweep its Milo scandal under the rug New York Knicks owner gave 0K to pro-Trump group Hannity apologizes for sharing 'inaccurate' story about McCain MORE (R-Ariz.) praised Clinton's handling of the situation via his Twitter account last Thursday, saying she did "a great job" getting the important supply lines open.