High-ranking Americans are gunned down in the place they thought was the safest in Afghanistan after days of rage over burnings of the Quran. NBC's Atia Abawi reports.
Updated at 5:40 a.m. ET: KABUL -- Afghan authorities told NBC News on Sunday that they believe an intelligence officer may have been involved in the alarmingly brazen killing of two senior U.S. Army officers at the country's Interior Ministry.
Sources told NBC that Abdul Saboor, 25, was a missing person and a suspect in the Saturday killing of a lieutenant colonel and a major, which took place as rage gripped the country for a fifth straight day over the burning of the Muslim holy book at a NATO base.
"Abdul Saboor is at large right now. He is the main suspect for us but we cannot draw any conclusions over whether or not he is the killer,'' sources told Reuters, adding that CCTV footage shows that Saboor had access to the Command and Control Center where the slain Americans were found.
A gunman shot the Americans as they sat at their desks inside the government ministry building, NBC News reported. They were shot in the back of the head, Western officials speaking on condition of anonymity told The Associated Press.
Saboor fled the ministry after the slayings, counter-terrorism officials earlier told the BBC.
Underscoring the gravity of the attack and apparent security breach, Gen. John Allen, the commander of NATO and U.S. forces in Afghanistan, ordered all NATO personnel recalled from Afghan ministries "for obvious force protection reasons."
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The NATO recall affects advisers numbered "in the low hundreds," said Lt. Col. Jimmie Cummings, a spokesman for the international force. Allen's unprecedented action in the decade-long war highlighted the growing friction between Afghans and their foreign partners at a critical juncture in the war.
Saboor's family were being interrogated, sources told NBC on Sunday.
A senior Afghan general told the BBC: ''The virus of infiltration has spread like a cancer and it needs an operation. Curing it has not helped."
The Taliban claimed responsibility for the Interior Ministry attack, saying it was retaliation for the Quran burnings, after the U.S. servicemen were found dead on the floor of an office that only people who know a numerical combination can get into, Afghan and Western officials said.
The U.S.-led coalition is trying to mentor and strengthen Afghan security forces so they can lead the fight against the Taliban and foreign troops can go home. That mission, however, requires a measure of trust at a time when anti-Western sentiment is at an all-time high.
About 30 people have been killed, including four U.S. soldiers, since the Quran-burning incident came to light Tuesday.
Afghanistan's president, meanwhile, renewed his calls for calm.
"Now is the time to return to calm and not let our enemies use this situation," Karzai said. Asked about the unprecedented recall of NATO staff, Karzai said it was an understandable step.
"It is a temporary step at a time when the people of Afghanistan are angry over the burning of the holy Quran," Karzai said. "We are not against this," he added.
NBC News, msnbc.com, Reuters and The Associated Press contributed to this report.
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