A car bomb exploded in the parking lot of the High Court building in northwestern Pakistan on Tuesday, killing one person and injuring six others, police and officials said.

The blast happened in Peshawar, the capital of North West Frontier Province, and most of the injured were passers-by, said Nihayat Ullah, a police investigator.

No one claimed responsibility for the attack, and Ullah said police were looking for the owner of the car.

Tila Mohammed, 22, a witness, told The Associated Press he heard a "deafening explosion" but did not see anyone planting the bomb.

"The blast was so powerful that I fell down. I saw people running in panic," he said.

Haji Ghulam Ali, the city mayor, had arrived to meet with some of his friends and said his car was damaged. "This is an action of terrorism, and I condemn those who carried out this attack," he said.

The vehicle where the bomb was planted was destroyed, and nearby cars were damaged. Police sealed off the site, and bomb disposal experts collected samples from the wreckage.

Seven people were taken to a hospital, where one died later, Ullah said.

Interior Ministry spokesman Brig. Javed Iqbal Cheema condemned the blast and recent attacks on security forces in tribal areas near the Afghan border, but said they would not deter the nation's resolve in fighting terrorism.

The blast came two weeks after a suicide bomber with a warning for American spies taped to his leg blew up a restaurant in Peshawar, killing 25 people in the old quarter of the frontier city synonymous with violent Islamic radicalism and political intrigue.

Security officials indicated the May 15 blast could be retaliation for the killing the previous weekend of Mullah Dadullah, the Taliban's military chief in nearby Afghanistan — a further sign the war between Islamic militants and NATO forces was spilling across the border.