LAHORE, Pakistan — Teams of gunmen attacked three law enforcement facilities across the eastern city of Lahore today, paralyzing Pakistan's cultural capital, while a car bomb devastated a northwest police station, killing a total of 38 people in an escalating wave of terror in this nuclear-armed U.S. ally.

Another bombing in the northwestern city of Peshawar later in the day wounded five people, further rattling the country.

The bloodshed, aimed at scuttling a planned offensive into the militant heartland along the Afghan border, highlights the militants' ability to carry out sophisticated strikes on heavily fortified facilities and exposes the failure of the intelligence agencies to adequately infiltrate the extremist cells.

No group immediately claimed responsibility, though suspicion fell on the Pakistani Taliban who have claimed other recent strikes. The attacks today also were the latest to underscore the growing threat to Punjab, the province next to India where the Taliban are believed to have made inroads and linked up with local insurgent outfits.

President Asif Ali Zardari said the bloodshed that has engulfed the nation over the past 11 days would not deter the government from its mission to eliminate the violent extremists, according to a statement on the state-run news agency.

"The enemy has started a guerrilla war," Interior Minister Rehman Malik said. "The whole nation should be united against these handful of terrorists, and God willing we will defeat them."

The wave of violence practically shut down daily life in Lahore. All government offices were ordered shut, the roads were nearly empty, major markets did not open and stores that had been open pulled down their shutters.

The assaults began just after 9 a.m. when a group of gunmen attacked a building housing the Federal Investigation Agency, a law enforcement branch that deals with matters ranging from immigration to terrorism.