KABUL, Afghanistan -- Two American soldiers and an American civilian working with them were killed in a so-called insider attack on Saturday in Afghanistan, officials said. In a second attack on international forces, an Italian soldier was killed when a grenade was thrown at him.
In the insider attack, which took place at a base in Paktika Province in the east near the border with Pakistan, a soldier with the Afghan National Army opened fire during lunchtime, killing the civilian and two American soldiers serving with him, according to Afghan military officers from the 203rd Thunder Corps. The international military coalition here confirmed that the attacker had been wearing an Afghan National Army uniform but, in keeping with military policy, did not specify the exact location or circumstances of the attack.
The gunman -- a company commander, according to Afghan soldiers on the base -- was killed almost immediately. In a statement released late Saturday, the military coalition, the International Security Assistance Force, said a second gunman had been detained, suggesting that two soldiers had conspired in the assault -- a relatively rare occurrence, since most insider attacks are by lone actors.
Afghan officials said an argument had precipitated the violence, which has been the case in other such attacks.
The Paktika governor's office released a statement saying that the shooting occurred after an argument between the Americans and the Afghan soldier who was killed. The argument was ostensibly over a decision not to allow the soldier to attend a shura, according to a Western official who had been briefed on the shooting. A shura is traditionally a meeting of Afghan elders, but it was not clear what kind of shura the gunman had been excluded from, and also unclear why that would lead the soldier to shoot at the Americans.
Gen. Zahir Azimi, an Afghan Defense Ministry spokesman, confirmed the shooting, but said he had little information about the gunman, in part because foreign troops quickly surrounded the area and the Afghans had not been able to investigate.
The international coalition fighting in Afghanistan has taken a number of steps over the last two years to protect its soldiers against insider attacks, and there have been just six this year, according to the ISAF.
ISAF officials have said they expect more attempts. It is not known how many of the attacks are carried out by Taliban plants within the security forces or by Taliban sympathizers, and how many are more random acts by disgruntled members of the Afghan forces who may hold grudges against their international counterparts.
Last year, 48 insider attacks killed 64 international troops and civilians working with the military.
The second attack on Saturday took place in Farah Province in western Afghanistan as two men on a motorcycle threw a grenade at a group of Italian soldiers, killing one and wounding two others, according to an early account by Abdul Rahman Zahwandi, a spokesman for the provincial governor. The attack took place as the convoy of Italians was heading back from the provincial capital, Farah, to an ISAF base nearby, he said.
"It happened in the capital, and there were crowds of people," Mr. Zahwandi said. "The two attackers managed to escape."
ISAF confirmed the death, but the exact circumstances were unclear. Other reports suggested that the Italians had been walking on a street after leaving their armored vehicle, which would have made them far more vulnerable to a grenade attack.
The Taliban praised the attack, while giving a very different account of it, but did not appear to be taking responsibility for it.
In a statement on the Taliban's Web site, the spokesman for the insurgents in the south and west of Afghanistan, Qari Yusuf, said: "A brave, heroic 11-year-old Afghan child hurled a hand grenade at dismounted Italian troops in Farah city today at 11 a.m. local time. As a result, one invader was killed and three others wounded. This incident clearly shows the utter hatred of Afghans towards the foreign invaders who have occupied our land for the past decade."
Taliban statements are often inaccurate, and this one could not be verified. Two days earlier, a Taliban attack killed seven Georgian soldiers in Helmand Province, the deadliest province for foreign troops in Afghanistan.
Farooq Jan Mangal contributed reporting from Khost, Afghanistan, and Taimoor Shah from Kandahar, Afghanistan.
This article originally appeared in The New York Times.