Official: Gunman in killing of U.S. soldiers identified as Afghan intelligence officer The desecration of Qurans at an U.S. base has sparked violent and deadly protests in Afghanistan. NEW: The Afghan president says 29 people have been killed in violent protests The gunman has been identified as Abdul Saboor, an Afghan official says Saboor is a junior officer at the Ministry of Interior who works in intelligence, the official says Authorities believe the shootings are related to the burning of Qurans Kabul, Afghanistan (CNN) -- A gunman who shot two American officers inside the highly secured Afghan Ministry of Interior was identified Sunday as a junior intelligence officer with ties to a Pakistani religious school, an Afghan counter-terrorism official said. Afghan authorities believe the shootings are tied to outrage over reports that NATO troops recently burned Qurans at a U.S. base, which sparked violent, deadly protests, shootings of four U.S. soldiers and an attack on a United Nations building. The gunman, who remained at large, was identified as Abdul Saboor, an employee in the ministry's intelligence department, according to the official, who spoke on condition of anonymity because he was not authorized to release the information. We believe it was 100% linked to the Quran burning because of the religious background of this junior officer. He spent two months in a Pakistani madrassa," the official said. The protests began last week after reports emerged that NATO troops burned Qurans at Bagram Airfield. American officials, including President Barack Obama, have apologized and said burning them was an unintentional error. In a televised address on Sunday, Karzai said 29 people died in the recent protests and called on Afghans to exercise restraint in their anger over the burning of the Qurans. "We have asked for punishment and an investigation," he said. Karzai also expressed sorrow over the killing of the American officers, but said he did not know who was responsible. At least four people died and 50 were wounded in a violent demonstration Saturday in Kunduz that saw protesters attempt to burn down a United Nations, Afghan authorities said. Saturday's killing of the American officers prompted Gen. John Allen to order several hundred NATO-led International Security Assistance Force advisers to withdraw from ministries in Kabul as a precaution, raising questions about a U.S. military plan that plans to focus on the use of small teams of military advisers as it withdraws troops. "For obvious force protection reasons, I have also taken immediate measures to recall all other ISAF personnel working in ministries in and around Kabul," Allen said. "We are aware of the media reports that are out there now, naming a suspect, but we have no new information from our ongoing investigation of yesterday's incident, regarding the shooter," said Lt. Col. Jimmie Cummings, an ISAF spokesman. Saboor, according to the Afghan official, arrived at the ministry Saturday about noon, signed himself in and retrieved his gun. The two officers were found dead in their office from gunshot wounds to the head, said an Afghan police official, who also spoke on condition of anonymity for the same reason. Despite being pulled from the ministries, the military advisers remained in contact with ministry personnel, Cummings said. "We will not let this incident divide the coalition," he said. Even so, NATO troops working as advisers outside the Afghan capital were also warned to take precautions. The warning follows reports of the shooting deaths of two American soldiers by a man wearing an Afghan National Army uniform at a base in the eastern Nangarhar province. The Defense Department over the weekend identified the two as Army Sgt. Joshua A. Born, 25, of Niceville, Florida, and Cpl. Timothy J. Conrad Jr., 22, of Roanoke, Virginia. Both were assigned to the 385th Military Police Battalion, 16th Military Police Brigade at Fort Stewart, Georgia. CNN's Chelsea J. Carter contributed to this report.