A suicide car bomber killed three policemen and a child today in an attack on a police station in a northwestern Pakistani town, police said.
Al-qa'ida-linked Pakistani militants have carried out numerous attacks on members of the security forces over the past couple of years, and they stepped up strikes after the army launched an offensive on their main bastion in October.
The blast in the town of Karak, 125 miles southwest of Islamabad, came as police were on the alert for attacks on religious processions to mark the anniversary of the Prophet Mohammad's birth.
"The blast destroyed part of police station and a nearby mosque," police official Gul Sadi Khan told Reuters, adding three policmen had been killed. "Thirteen people have been wounded and we fear more people are trapped under the debris."
Another police official said a child passer-by had also been killed.
Karak is in North West Frontier Province, which has borne the brunt of attacks over the past year.
The Pakistani Taliban, allies of the Afghan Taliban, have lost much ground in army offensives over the past year.
The were pushed out of the Swat valley, northwest of Islamabad, and in October the army began a big offensive in the militants' South Waziristan bastion on the Afghan border.
Pakistani action against militants on the border is seen as crucial for efforts to bring stability to Afghanistan, where US forces are spearheading one of NATO's biggest offensive against the Afghan Taliban.
Fears of militant attacks on the Saturday holiday hurt trade in Pakistani stocks the previous day with the Karachi Stock Exchange benchmark 100-share index slipping 0.1 percent, as other regional markets rose, and turnover at a 2-month low.
Fifty-seven people were killed in Karachi in a militant attack on a Muslim congregation marking the holiday in 2006.
The attack sparked violence in Pakistan's commercial capital and the stock exchange shut for a day.