A leaked video showing the pilot of an American helicopter happily singing while a US missile hits an Afghan man is set to further embarrass the United States.

The video, leaked on LiveLeak.com purportedly shows an pilot from the 101st Airborne Division in an AH64 Apache helicopter firing a missile on July 4.

At the moment of impact the pilot can be heard singing Bye Bye Miss American Pie.

Just as he belts out the most famous line of Don McLean's classic song American Pie, the missiles explodes. Another pilot can also be heard saying "nice" after the explosion.

The video was taken from the Apache helicopter's on-board camera and during a US patrol in the Wardak province, west of the capital Kabul, the web site claims.

The victims hit by the missiles were just "innocent farmers planting poppy seeds in the middle of the road", it adds. This information has not been verified or confirmed.

Two other victims can be seen running in a bid to avoid the missiles as pilots continue to shoot at them.

After the strike two other victims can be seen running for their lives

LiveLeak was rapidly inundated by comments, with people's reactions ranging from ones of disgust to anger.

"Is there any evidence at all that these people were doing anything wrong? Of course not, but that doesn't stop our criminal government from bombing them, now does it?" a comment read.

"It's disturbing and bordering on sanctioned psychopathy to enjoy killing so much', another said.

The 101st Airborne Division, also known as the "Screaming Eagles" is trained for air assault operations.

It is renowned for its role in helping fight the German Nazi regime during the Second World War but also conducted a series of high profile campaigns during the Vietnam war and the first gulf war.

Embarrassing footage

It is not the first time an embarrassing footage is posted online. In January a video showing soldiers in US uniforms urinating on three Taliban corpses provoked uproar.

In the footage, one of the men can be heard saying: "Have a great day, buddy" as they urinate while another soldier chuckles.

A third officer also joked: "Golden like a shower".

The video angered Afghans and put further strain on the US-Afghanistan relationship.

The US also landed in trouble after it emerged that five U.S. service members were involved in the incineration of a pile of Korans in Afghanistan in April.

The move provoked widespread anger, leading to unrest as tensions escalated after demonstrators held a series of protests.