(Releads with Interior Ministry statement)

By Mian Khursheed

ISLAMABAD, July 6 (Reuters) - Shots were fired from the rooftop of a house overflown by Pakistan President Pervez Musharraf's aircraft as it took off from Rawalpindi on Friday, but the government was unable to say if the plane was targeted.

Musharraf's plane arrived safely in the southwestern town of Turbat.

The gunfire came from a sub-machine gun with a telescope, and two anti-aircraft guns were found on the roof of the house, but the government said it had not established any link with the take-off of the president's plane to visit flood hit areas of southwest Pakistan.

"A definite answer will only be available on completion of the investigations," said a statement released by the Ministry of the Interior.

The two anti-aircraft guns had not been fired. The house was located close to the runway, where the plane would still be gaining altitude.

But an intelligence officer, speaking on condition of anonymity, said there had been an unsuccessful attempt on Musharraf's life.

"There was an attempt, that was missed," said the officer.

U.S. ally Musharraf, who came to power in a military coup in 1999, survived two assassination attempts by al Qaeda-linked militants in Rawalpindi in December 2003.

Security is normally deployed in the area ahead of the president's flights, the timings of which are kept secret.

Neighbour Arshad Mehmood said he heard the firing. He said the house had been vacant and up for rent, though a couple with two children had visited it the previous night.

Security forces cordoned off the area around the house in the garrison town next to the capital, Islamabad, and the owner, a shopkeeper, was detained.

According to some television reports a rocket was also fired at the plane, but the Interior Ministry denied that.

Musharraf, who came to power in a military coup in 1999, has been a hated figure among Pakistani militant groups since he abandoned support for the Taliban and sought peace with India over the disputed territory of Kashmir.

The Rawalpindi shooting came as Pakistani security forces laid siege to a mosque in Islamabad where a radical cleric and hundreds of followers were holed up after clashes on Tuesday.

At least 19 people have been killed so far in the clashes and bloody stand-off.

Washington has depended on General Musharraf to help crush Osama bin Laden's network, the remnants of which have been regrouping in Pakistan's tribal areas on the Afghan border.

The Pakistan army's support is crucial also to the success of a NATO counter-insurgency campaign against the Taliban in Afghanistan.

Coincidentally, the plane of Mohammad Zia-ul-Haq, another Pakistani president who came from the military and was allied to the United States, was fired on as it overflew the same neighbourhood in the 1980s.

Zia later died in a mysterious aircrash, along with the U.S. ambassador. There has long been speculation enemies inside the military assassinated him. (Writing by Simon Cameron-Moore, editing by Jerry Norton; Reuters Messaging: cameron.moore.reuters.com@reuters.net))

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