Three US Marines gunned down by traitor Afghan police commander who invited them to dinner - and it's the THIRD such deadly betrayal of allied forces in a week

Three members of America's special operation forces killed by Afghan solider after he invited them to security meeting



U.S. soldier killed and two others injured on attack by Afghan soldier on Tuesday



On Wednesday suicide bombers in Kunar province killed three NATO members and one Afghan civilian

Thursday Afghan soldiers tried to gun down NATO troops; an Afghan soldier was killed

31 coalition service members killed by Afghan forces or insurgents this year



An Afghan police officer shot and killed three U.S. Marines after sharing a meal with them before dawn Friday and then fled into the desolate darkness of southern Afghanistan, the third attack on coalition forces by their Afghan counterparts in a week.



The Afghan police commander opened fire on the three Americans after inviting them to dinner at his outpost under the pretext of having a meeting to discuss security.

Thirty-one coalition service members have now died this year at the hands of Afghan forces or insurgents disguised in Afghan uniforms, according to NATO — a dramatic rise from previous years.



The assaults have cast a shadow of fear and mistrust over U.S. efforts to train Afghan soldiers and police more than 10 years after the U.S.-led invasion to topple the Taliban's hardline Islamist regime for sheltering al-Qaida's leadership.



Scroll down for video

Working together: NATO troops are training and working alongside Afghan soldiers as they take increasing responsibility for the anti-insurgency campaign. Afghanistan's National Army (ANA) soldiers march during a graduation ceremony at a training center in Herat on August 9, 2012. The attack which killed three soldiers this morning is the latest in a series of so-called green-on-blue attacks in Afghanistan. The Afghan soldiers in the picture are not related to the incident

The attacks also raise further doubts about the quality of the Afghan forces taking over in many areas before most international troops leave the country in 2014.

Friday's deadly shooting - in which another service member was injured - took place in the volatile Sangin district of Helmand province.



Sangin was a Taliban stronghold for years and has one of the highest concentrations of improvised explosive devices, or IEDs, in the country.



Sangin's district chief and the Taliban both identified the gunman as Asadullah, a member of the Afghan National Police who was helping the Marines train the Afghan Local Police.



Taliban spokesman Qari Yousef Ahmadi said by telephone that the attacker joined the insurgency after the shooting.



'Now, he is with us,' Ahmadi said.



The district chief, Mohammad Sharif, said the shooting happened at a police checkpoint after a joint meal and a security meeting. The meal took place before dawn because of Ramadan, the month in which Muslims abstain from food during daylight hours.



Also at the dinner were recruits to the Afghan Local Police, a village militia being trained by American special forces, according to an Afghan official.



'It looks like he had drawn up a plan to kill them previously,' an Afghan official said of the lone shooter. It is not clear if he was wearing military or police uniform during the attack.



The attack is the third killing this week of coalition soldiers by Afghans they are training to take over responsibility for security once most international forces leave in 2014.



The recent spate of deadly attacks will undoubtedly also cause a headache for Barack Obama in the run-up to November's presidential election.



Members of the Afghan National Army (ANA) soldiers stand guard in Laghman province as NATO troops train them in preparation for their withdrawal in 2014

Last year, a U.S. Army team led by a behavioral scientist produced a 70-page survey that revealed both Afghan and American soldiers hold disturbingly negative perceptions of the other.

According to the survey, many Afghan security personnel found U.S. troops 'extremely arrogant, bullying and unwilling to listen to their advice' and sometimes lacking concern about Afghans' safety in combat. They accused the Americans of ignoring female privacy and using denigrating names for Afghans.

American troops, in turn, often accused Afghan troops and police of 'pervasive illicit drug use, massive thievery, personal instability, dishonesty, no integrity,' the survey, which has been downplayed by U.S. military officials, said.

The U.S. hopes the Afghan Local Police, a village defense force backed by the national government, will become a key force in fighting the insurgency.

Just last month, a coalition statement touted the Marines' work training the Afghan Local Police in Sangin, describing a new academy in an Afghan National Police compound near a Marines base.

'During the three-week course, future police train in the basics of patrolling, vehicle and personnel searches, checkpoints, escalation of force, detainee procedures, marksmanship and Afghan law,' the statement said. 'After completing training, the new ALP are stationed at patrol bases in their hometowns.'

Meanwhile Friday, Britain said one of its soldiers died the previous day from wounds he received in a shooting while on patrol in the Nad Ali district of Helmand province . The death brings to 19 the number of coalition troops killed in Afghanistan this month.

And elsewhere in Helmand province Friday, six Afghan civilians were killed when their car hit a roadside bomb, one of thousands planted by insurgents across the volatile region. Helmand police official Mohammad Ismail Khan said the bomb killed three children, two women and a man.

Last night's attack came at the end of a week of violence; on Tuesday, two gunmen wearing Afghan army uniforms killed a U.S. soldier and wounded two others in Paktia province in the east.

The Taliban took responsibility for the attack. The gunmen escaped after the shooting and a search is underway to track them down.

Victims: Thomas E. Kennedy, 35, left, and Sgt. Maj. Kevin Griffin, 45, were killed in a twin suicide attack in the Kunar province on Wednesday. The troops were assigned to units based at Fort Carson in Colorado



Killed: Walter D. Gray died in Wednesday's suicide bombing attack

On Wednesday, suicide bombers killed three members of a Nato patrol and an American working for the State Department's ASAID programme in eastern Afghanistan.



The Taliban has claimed responsibility for the bombing which happened in Kunar province, an eastern stronghold of the insurgency that lies along the volatile border with Pakistan where militants have hideouts.

Two attackers wearing suicide vests detonated their explosives as a Nato foot patrol passed by the headquarters of the provincial government.

The U.S. government identified the four Americans killed earlier in the week. Secretary of State Hillary Rodham Clinton's statement said USAID foreign service officer Ragaei Abdelfattah, three coalition service members and an Afghan civilian were killed. A State Department diplomat was injured.

The Defense Department identified the three troops killed in Kunar as Air Force Maj. Walter D. Gray, of Conyers, Ga.; Army Maj. Thomas E. Kennedy, of West Point, N.Y.; and Command Sgt. Maj. Kevin J. Griffin, of Laramie, Wyo.

And on Thursday, two Afghan soldiers tried to gun down a group of NATO troops outside a military base in eastern Afghanistan. No international forces were killed, but one of the attackers was killed as NATO forces shot back.

This year has seen a rising number of so-called 'green-on-blue' attacks in which Afghan security forces, or insurgents disguised in their uniforms, kill their U.S. or NATO partners.

So far this year, 30 coalition troops have been killed in 20 such attacks. That compares with 11 fatal attacks and 20 deaths the previous year. In 2007 and 2008 there was a combined total of four attacks and four deaths.

The worrying rise in 'green-on-blue' attacks raises questions over the merit of U.S. troops training Afghan police and soldiers in order to hand over security responsibilities come 2014.

This mentoring means Western troops living and working in very close quarters with their Afghan counterparts.

Both coalition and Afghan officials say that the majority of the attacks are because of personal antagonism between the counterparts rather than being the result of Taliban infiltration.

Deadly week: On Tuesday two gunman wearing Afghan army uniforms killed a U.S. soldier in the Paktia province. Four Americans died on Wednesday in a suicide bombing attack in the Kunar province

Brig. Gen. Gunter Katz described Friday’s attack as ‘tragic’ but told CBS is did not reflect the ‘security situation’ calling the shooting an ‘isolated incident.’

DEADLY WEEK IN AFGHANISTAN

This week in Afghanistan has been particularly violent with eight Americans, including one civilian, killed in three separate attacks.

On Tuesday, two gunmen wearing Afghan army uniforms killed a U.S. soldier and wounded two others in Paktia province in the east.

Suicide bombers killed three members of a Nato patrol and an American working for the State Department's ASAID programme in the Kunar province in eastern Afghanistan on Wednesday.

On Thursday two Afghan soldiers tried to gun down a group of NATO troops outside a military base in eastern Afghanistan.One of the attackers was killed as NATO forces shot back.

Friday morning in Helmand province, an Afghan police commander lured three U.S. special forces to their death by inviting them to dinner. He then opened fire killing three and injuring one.

The Taliban say the shooter fled and joined their forces.

In another incident, NATO said a coalition service member died after an insurgent attack in southern Afghanistan. The death brings to 19 the number of coalition troops killed in Afghanistan this month.



Also in Helmand province Friday, six Afghan civilians were killed when their car hit a roadside bomb.

'We're confident this won't stop operations,' the ISAF spokesman told CBS. 'We trust our Afghan partners. But we're looking at how to mitigate incidents.'

Katz detailed the Afghan security forces extensive vetting process which involves recruits getting two character references from local elders, as well as biometric, medical and drug tests.

Nonetheless, with the increase of ‘green-on-blue’ attacks destroying trust between the coalition and Afghan troops, U.S. units now select a ‘guardian angel’ to watch over fellow troops - including when they sleep - at the joint bases.



Meanwhile, on Tuesday, the Taliban released a sickening video showing an Afghan soldier who killed a U.S. soldier and injured two others being welcomed back into the insurgent encampment.



On May 11 the soldier – who the Taliban named as Mamood – turned on his American trainers and opened fire.



First Lt Alejo Thompson, a father of two young children, was killed in the ambush in eastern Afghanistan.



The disturbing video shows the soldier being hailed as a hero. Elders embrace him and adorn him with necklaces strung with flowers. They congratulate him on his deed as he smiles for the camera.

















VIDEO: NATO Spokesman discusses the killings...

Watch video of Taliban 'welcome' here