ISLAMABAD, Sept 3 Shots fired by snipers hiding on a hill by the Islamabad Highway hit one of the cars used by Prime Minister Yousuf Raza Gilani on Wednesday when his motorcade was going to the airport to pick him up.

Sources said two bullets hit the driver's window of one of the three bullet-proof cars used by the prime minister.

Apparently, the prime minister was the target, but there was a possibility that the act was aimed merely at sounding a warning, the sources said.

They termed it a highly-skilled sniping attempt because the vehicles were moving at high speed.

They said it appeared that three gunmen had attacked the motorcade from both sides of the highway, but only the snipers hiding on a hill known as “Numberon wali pahari” succeeded in hitting the car. A portrait of the Father of the Nation dominates the hill, with his saying “Unity, Faith and Discipline” emblazoned on it.

The incident took place about a kilometre away from the spot where a procession of the Pakistan Muslim League-N had come under attack on Dec 27, hours before Benazir Bhutto's assassination.

Although the prime minister was not in the motorcade at the time of the attack, officials described it as an assassination attempt.

The sources quoted Pervez, the driver of the vehicle which was hit, as saying “I observed cracks and two gunshots on the window when I reached the airport at around 1.30pm to receive the PM and his delegation.”

The VVIP motorcade drove back to the Prime Minister's House and the driver narrated the incident to the authorities concerned. The PM's House informed Islamabad police about the incident, but it tried to pass the buck to Rawalpindi police, claiming that the incident had taken place in an area falling under the jurisdiction of the Pindi administration.

However, its officers visited the spot more than an hour later and interrogated people living in the vicinity.

Later, a joint investigation team, led by National Police Bureau's Director General Tariq Khosa, also arrived at the spot and started investigations.

Three people were taken into custody near the hill, sources said.

Senior Superintendent of Police Ahmad Latif said it was too early to comment on the incident. Forensic experts would inspect the vehicle to find out whether the window had been damaged by bullets or stones.

PM HOUSE VERSION A statement issued by the Prime Minister's House said unknown assailants attacked the motorcade of Mr Gilani on the Islamabad Highway in the afternoon.

Of the multiple sniper shots fired on the vehicle, two hit the window on the driver's side. However, “because of the robust and comprehensive security measures”, the prime minister and all the members of his motorcade remained unharmed, the statement said.

A high-level inquiry had been initiated into the matter and all law-enforcement agencies had begun working on the case, it said. “Experts are reviewing the security arrangements and looking into lapses.”

Late in the evening, the investigators stopped search for evidence in the area from where the attack was purported to have been carried out because of darkness. They failed to find any shells of bullets, but the search would resume on Thursday morning, an official said.