ISLAMABAD, Pakistan: Pakistan's presidential front runner has moved into a tightly guarded government compound over security fears, officials said Friday as a militant campaign against the government led to more violence in the country's volatile northwest.

The party of Asif Ali Zardari, the widower of slain ex Prime Minister Benazir Bhutto, has sought to assure the U. S. since Pervez Musharraf's ouster as president that it is committed to battling terrorists.

The country has been hit by a string of suicide bombings this month, including one last week that left 67 dead, many of them civilians.

Prime Minister Yousaf Raza Gilani told reporters Friday that Zardari - who is widely expected to win a September 6 presidential election by lawmakers - was staying at a hilltop mansion in Islamabad s government quarters "for security reasons."

He did not elaborate, but an intelligence official said there had been reports that the presidential hopeful could be the target of an attack and that he had switched locations after Musharraf's August 18 resignation.

The official spoke on condition of anonymity because of the sensitivity of the subject.

Pakistan's 5-month-old civilian government initially sought to calm militant violence by holding peace talks, something Musharraf briefly tried as well. But it has increasingly intensified military action against al Qaida and Taliban linked militants in tribal regions along the Afghan border, a rumored hide out of Osama bin Laden, reportedly killing hundreds in recent weeks.

The militants, who have been pounded by helicopter gunships, have threatened more suicide bombings unless the operations cease. They have hit one of the country's largest military installations, a hospital and a police station in the last week.

Paramilitary troops foiled a suicide attack aimed at a building housing security forces near a vital tunnel in the northwestern region of Kohat Friday. The troops fired on an explosive laden car after the driver sped through a checkpoint, said Rasheed Khan, a government official.

Four civilians were killed in the explosion, he said, and 28 people were wounded, most of them security forces.

Suspected militants also blew up two bridges in the area, said Kohat district administrator Mohammad Siraj Khan.

The U. S. worries that violence and political instability that followed Musharraf's resignation after nearly nine years in power would distract the nuclear armed nation's efforts to fight extremists.

Adm. Mike Mullen, chairman of the U. S. Joint Chiefs of Staff, conducted a secret strategy session with Gen. Ashfaq Kayani, Pakistan's army chief, on an aircraft carrier in the Indian Ocean this week.

They focused on the problem of militants using the country as a safe haven for cross border attacks on U. S. allied troops in Afghanistan, officials said. 

Source : AP