Clashes broke out Friday between Pakistani troops and militants in North Waziristan after a homicide car bomber hit a security checkpoint, killing four people, officials said.

The attack on the outskirts of the main town of Miran Shah, which killed a soldier and three male civilians, came hours after a 45-member delegation of tribal elders began talks with pro-Taliban militant leaders to resurrect a controversial peace deal and stem spiraling violence.

Homicide attacks, shootings and a siege and army raid on a mosque in Islamabad have killed about 289 people in Pakistan so far this month, raising concern about the threat posed by Islamic extremists and the country's political stability.

The latest attack comes a day after three suicide bombings killed at least 51 people.

As the tribal elders were meeting with militant leaders in Miran Shah, a man detonated the car bomb when asked to stop at a checkpoint, according to two local security officials.

The officials, who spoke on condition of anonymity because they were not authorized to speak to journalists, said security forces backed by a helicopter gunship raided an alleged militant hide-out, triggering a shootout. It was not immediately clear whether the militants suffered casualties.

Violence has spread from Pakistan's tribal areas to the capital and elsewhere since last week when militants abandoned a 2006 peace deal they signed with the government to stop attacks on troops and officials.

The militants ended the agreement after the army's bloody assault on Islamabad's Red Mosque last week.

On Friday, tribal elder Malik Nasrullah told The Associated Press before entering talks with militant leaders he was "optimistic" the peace deal with the government could be revived.

"We will meet with them to request that they reverse their decision to end the peace agreement," said Nasrullah.

The government has attached high hopes to the success of the peace talks despite criticism from the United States that it has allowed more freedom for al-Qaida to base itself at the frontier.

The meeting came a day after a Homicide bomber driving a car hit a convoy carrying Chinese workers, killing 29 Pakistani bystanders and police, and prompting Musharraf to call for national unity against extremists.

Thursday's attack targeting a minibus carrying about 10 Chinese technicians occurred as their convoy was passing through the main bazaar in Hub, a town in Baluchistan province near the southern port city of Karachi.

Later Thursday, a homicide attacker detonated a bomb at a mosque in an army cantonment in the northwestern town of Kohat, killing at least 15 people, officials said.

Also Thursday, a homicide car bomber detonated his explosives when guards prevented him from entering the parade ground of a police academy in another northwestern town, Hangu. Six bystanders and one policeman died.