Islamabad  - At least 18 people, including 15 militants, were killed in overnight security operations and clashes between Taliban and local tribesmen in north-west Pakistan, officials said on Tuesday.

Seven Islamist militants died in an exchange of gun and artillery fire by security forces in the Kabal area of Swat district, where troops are fighting the followers of a militant cleric Maulana Fazlullah.

Fazlullah has waged an armed struggle to enforce Taliban rule in the area since late last year.

"One soldier was killed separately when the miscreants ambushed an army patrol in Kanjo area, while four were injured," local army spokesman Colonel Nadeem Ahmad told Deutsche Presse-Agentur dpa.

Following the ambush law enforcers arrested 27 suspected militants in Swat, formerly a popular tourist destination in North West frontier Province (NWFP).

In Charsadda, another district of troubled NWFP, Taliban fighters opened fire on a security convoy heading for search and cordon operation in Miian Kalley area.

"The forces repelled the attack and five militants were killed and five more injured in cross-firing," police investigator Marjan Ali told dpa. "Three were arrested," he added.

Three Islamist insurgents and two local tribesmen died in hours-long clashes in the tribal district of Bajaur, where the local population has raised laskhars, or traditional armies, to assist Pakistani troops fighting Taliban and al-Qaeda insurgents since early August.

The firefight started Monday afternoon when the militants ambushed several tribal elders who were on their way to the district's main town, Khar, to attend a meeting of a local jirga, or tribal council, against the Taliban.

"The exchange of fire that took place in Inayat Kalley continued late (into) the night," said local government official Israr Khan. "Two tribal elders and three Taliban died in the fighting."

According to the official, the Taliban abducted another tribal leader, Ismaeel Khan, who provided shelter to the tribesmen loyal to the government during the clashes. Three of his comrades were also seized.

The government claimed last month that more than 1,500 insurgents and 70 security personnel had died in the government offensive in Bajaur, from where militants launch cross-border attacks on international forces in the neighbouring Afghan province of Kunar. (dpa)