Islamabad  - A roadside bomb early on Friday killed three police officers and wounded six more in Pakistan's troubled north-western city of Peshawar, police said.

The casualties occurred when a police vehicle on patrol was hit by a remote-controlled bomb in the city's Yakka Toot neighbourhood.

"Two policemen died at the scene while one more died in the hospital," local police officer Abdul Qadir said.

The blast took place hours after a suicide bomber on foot detonated his explosives at the gates of a court complex in Peshawar, killing at least 19 people.

Three policemen who intercepted the attacker on Thursday morning were among the dead.

Islamist militants have stepped up attacks in Pakistani towns and cities after the security forces launched an offensive against the Taliban network in their South Waziristan heartland on October 17.

Their main target remains Peshawar, the capital of Pakistan's North-West Frontier Province which is close to the tribal areas.

Government officials have vowed to press ahead with the assault in Waziristan, a rugged region near the Afghan border with scores of sanctuaries for Taliban and al-Qaeda fighters. (dpa)