Pfc. Jarrod A. Lallier was gunned down last Monday by men who were wearing the uniforms of his allies.

The 20-year-old Fort Bragg paratrooper died when three men in Afghan police uniforms fired on a group of soldiers with small arms and a rocket-propelled grenade launcher, military officials said.

The men who killed Lallier escaped, so it isn't clear whether they were actually Afghan police or Taliban militants in stolen uniforms.

But the attack underscored the difficulty of arming and training Afghans to hold off the Taliban on their own. Dozens of attacks in which Afghan security forces have turned their weapons on their allies have eroded trust.

In one of those attacks earlier this year, two other Fort Bragg soldiers died. Staff Sgt. Jordan Bear and Spc. Payton Jones were shot to death in March.

Like Lallier, they were members of the 82nd Airborne Division's 4th Brigade Combat Team.

In April, a Fayetteville Observer reporter and photographer spent two weeks with the 4th Brigade in Afghanistan in an area of Kandahar where all three of the 82nd soldiers died.

The paratroopers they saw were training Afghan security forces and patrolling with them without incident.

But those soldiers described a sometimes-uneasy relationship with the Afghans -- distrust that is just one more hurdle in the difficult mission of getting out of Afghanistan without leaving behind a country that will sink into lawlessness.

Less than a mile from Combat Outpost Zarif Khel, an Army minesweeper halted the single-file line of soldiers trailing behind him.

Within seconds, a small, wiry Afghan was on his hands and knees, scooping dirt aside while stabbing at the ground with a knife.

The Afghan, a member of the local police force, was searching for an improvised explosive device.

In the Zharay district of Kandahar province -- where the Taliban originated -- IEDs are the top threat.

American troops in Zharay have adjusted their patrols and operating procedures to limit the effectiveness of the bombs -- walking in straight lines, never taking the "easy route" and always traveling with equipment that can detect them.

But the wiry Afghan, who never said a word to the group during the joint Afghan-U.S. patrol, might have been their best protection, according to several of the paratroopers.

Only half in jest, some soldiers said he may also be one of their biggest enemies.

"He's the best mine hound we have," a soldier said following a routine foot patrol outside the base. "He also may be setting half the bombs he finds."

The comment was a joke at the end of a patrol on a hot, dusty day. But it demonstrates the uneasiness provoked by attacks on American soldiers by supposedly friendly Afghans.

Afghan security forces have turned their weapons on their allies nearly 60 times since 2007, with roughly a third happening so far this year, according to published reports.

Bear and Jones, the 82nd paratroopers, died in a wave of such attacks that happened after American soldiers mistakenly burned Qurans taken from Afghan detainees.

The two soldiers were killed when three Afghan nationals -- two soldiers and a teacher -- fired at them from a guard tower, according to the U.S. military. Officials in Afghanistan said the shooters fired indiscriminately.

Hours after learning that two of their brigade comrades had been killed by supposed Afghan allies, a group of soldiers at Forward Operating Base Pasab had unexpected visitors.

The soldiers, who work as welders for the 782nd Brigade Support Battalion, 4th Brigade Combat Team, had a group of their students -- Afghan soldiers -- ask them to lunch.

Speaking weeks later, Chief Warrant Officer 2 Bill Wencil said he and the other soldiers were uncertain if the lunch was in response to the killings of Bear and Jones. He said the topic never came up.

While admitting that the soldiers kept their rifles ready during the lunch, Wencil praised the relationship between his soldiers and their Afghan allies.

"It's been really good to have them around every single day," he said. "We can go eat chow together. Maybe next time we'll have a volleyball game."

British Brig. Gen. Richard Cripwell, who heads the international effort to turn the mission over to the Afghans, said Wednesday that the high-profile attacks have done little to slow the transition.

"Any death out here is an absolute tragedy, and it is more so when it is caused by Afghan forces," Cripwell told reporters during a Pentagon briefing.

"But I should be clear, firstly, that it's a tragedy as much for the Afghans themselves," Cripwell added. "Every single day, there are tens of thousands and more ongoing relationships between ISAF (International Security Assistance Force) forces and the Afghans. We work extremely closely. We work extremely well together. These attacks are absolutely not representative of the huge, huge majority of the Afghan forces, and they are dismayed by them as we are."

Cripwell said the Afghan government is working to prevent insurgents from slipping into its military or police ranks.

"They are turning every stone they can to ensure the loyalty of their own forces," he said.

Cripwell said that the day-in, day-out relationships between Afghan and coalition forces were working extremely well.

"We are going on operations with them every day," he said. "There is absolutely no lack of trust between us and our Afghan colleagues."

Soldiers with the 82nd at Forward Operating Base Azizullah got a demonstration early in their deployment of the shame that some Afghans feel when their troops behave dishonorably.

The chaplain for the 2nd Battalion, 321st Field Artillery arrived at the base chapel to find an Afghan soldier rifling through his belongings, according to battalion commander Lt. Col. Philip Raymond.

The Afghan soldier was chased to his own compound, where he was seized by his own forces and punished with a beating.

Raymond said that later that day, the Afghan commander came to him with tears in his eyes, mortified and begging for forgiveness.

Raymond said the incident did not damage relationships on Azizullah and said that both American and Afghan leaders have done their best to quell any problems as they arise.

"It's human nature to have disagreements," Raymond said. "But we have to get over our egos. Distrust can fracture a team."

Raymond said many issues can be avoided with a little cultural sensitivity.

"It's honestly giving a durn about who they are," he said. "It's realizing that soldiers are soldiers. By the end of an air assault, everybody looks the same, smells the same and acts the same."

Lallier, the paratrooper killed Monday, was a member of the 1st Battalion of the 508th Parachute Infantry Regiment. The battalion works out of Forward Operating Base Pasab, which often serves as a hub of sorts for American troops traveling across the districts of Zharay and Maiwand.

Pasab is home to two Afghan National Army compounds. It's also the home of the 4th Brigade Combat Team's headquarters in Afghanistan. In the brigade's offices, American officers work across the hall from their Afghan counterparts.

"Shona ba shona" -- Pashto for "shoulder by shoulder" -- is an unofficial motto for 4th Brigade leaders, who have preached cooperation and cultural understanding.

It is a motto that has been tested by the actions of soldiers on both sides of the alliance this year.

A week after Bear and Jones were killed, an American soldier -- Staff Sgt. Robert Bales -- allegedly snuck off his base and killed 16 Afghan civilians in Kandahar's Panjwai district. Many of them were children.

Bales, who served with a unit based in Washington state, isn't representative of the coalition soldiers in Afghanistan. Cripwell, the British general, and other coalition soldiers acknowledge that the Afghans who turn on their allies are not representative of the thousands who have joined the tough fight to turn back the Taliban.

Fort Bragg soldiers were instructed not to speak about the Bales case to reporters. But they were certainly conscious of the incident as they discussed their efforts to build a strong working relationship with the Afghans.

"They have their good and their bad," said Capt. CeCe Carlson, a soldier with the 4th Brigade Combat Team. "We can't judge everybody on the actions of a few. I hope they don't judge us on the actions of a few."