Press TV reports: The US says the Pakistani army and the American troops have exchanged fire near the Afghan border after tensions over incursions flared.

The latest incident took place along the Pakistani border with the eastern Afghan region of Khost on late Thursday.

A senior US military official said skirmishes broke out after Pakistani soldiers fired warning shots near two US helicopters.

US Central Command spokesman Rear Admiral Gregory Smith said Pakistani soldiers at a border checkpoint were observed firing on two US OH-58 Kiowa helicopters covering a patrol of Afghan and US troops about a mile and a half inside Afghanistan.

“The ground forces then fired into the hillside nearby that checkpoint, gained their attention, which worked,” Smith added.

“Unfortunately, though, the Pak unit decided to shoot down a hillside at our ground forces. Our ground forces returned fire,” he noticed.

The incident on Thursday marks the first time US officials have confirmed an attack by Pakistani forces and exchange of fire.

The incident came just days after a pilotless US drone was shot down in the northwestern Pakistan when local tribes and Pakistani troops fired at the plane while crossing the border, local media reports said. The US denied the report.

Meanwhile, the tactic to mount counter-terrorist operations inside Pakistan has met with fierce opposition.

Anger in Pakistan has been rising since the US began conducting cross-border commando raids as well as stepping up the number of attacks from unmanned Predator drones in the tribal region.

US Predator drones usually armed with missiles have killed dozens of Pakistani civilians during recent weeks.

Pakistani leaders including the president and premier have lashed out at the United States over alleged violation of its air and ground space and killing of innocent civilians.

President Asif Ali Zardari said Thursday that Pakistan’s military is firing “flares” to warn NATO helicopters about the exact location of Pakistan’s border with Afghanistan.

Later, Zardari launched his verbal attacks at the United States at his UN speech over alleged violation of air and ground space on the border with Afghanistan.

Premier Seyed Yousuf Raza Gilani earlier reiterated that his country would not tolerate violations of its sovereignty after a series of strikes in recent weeks.

The experts say Zardari’s speech and Gilani’s comments underscore significant tensions between the so-called “war on terror” allies.

The political analysts say that border clashes have added to US-Pak Tensions.

They also believe though there’s no war going on between the US and Pakistan yet, but recent exchanges involving American and Pakistani forces along the Pak-Afghan frontier are sounding like a sputtering fuse that’s growing ever shorter.

Some others also fear break out of an all-out war between the two countries after the relations reached at its lowest level since last sixty years.