Updated

Teams of gunmen launched coordinated attacks on three law enforcement facilities in Pakistan's eastern city of Lahore and car bombs hit two other cities Thursday, including an attack outside a Peshawar school. The day's violence claimed the lives of at least 39 people in an escalating wave of anti-government attacks.

The bloodshed, aimed at scuttling a planned offensive into the Taliban heartland near the Afghan border, highlights the Islamist 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 Thursday 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.

SLIDESHOW: Bloody Violence in Pakistan (Graphic)

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.

"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 and major markets were closed.

The assaults began about 9 a.m. when a group of gunmen attacked the Federal Investigation Agency, the national law enforcement body.

The attack lasted about 1 1/2 hours and ended with the death of two assailants, four government employees and a bystander, senior official Sajjad Bhutta said. Police official Chaudhry Shafiq said one of the dead wore a homicide vest.

A second band of gunman then raided a police training school on the outskirts of the city, killing nine police officers, officials said. Police killed one gunmen and the other three blew themselves up.

A third team then scaled the back wall of a police commando training center near the airport, Lahore police chief Pervez Rathore said. The attackers stood on the roof of a house, shooting at security forces and throwing grenades, said Lt. Gen. Shafqat Ahmad, the top military officer in Lahore.

Two attackers were slain in the gunbattle and three blew themselves up, he said. A police nursing assistant and a civilian also died, he said.

TV footage showed helicopters in the air over one of the police facilities and paramilitary forces with rifles and bulletproof vests taking cover behind trees outside the compound's wall.

Officials have warned that Taliban fighters close to the border, Punjabi militants spread out across the country and foreign al-Qaida operatives were increasingly joining forces, dramatically increasing the dangers to Pakistan. Punjab is Pakistan's most populous and powerful province, and the Taliban claimed recently that they were activating cells there and elsewhere in the country for assaults.

An official at the provincial Punjab government's main intelligence agency said they had precise information about expected attacks on security targets and alerted police this week, but the assailants still managed to strike. The official spoke on condition of anonymity because he was not authorized to comment on the situation.

Despite their reach and influence, the nation's feared spy agencies have failed to stop the bloody attacks plaguing the country.

Kamran Bokhari, an analyst with Stratfor, a U.S.-based global intelligence firm, said Pakistan needed to penetrate more militant groups and intercept conversations to prevent attacks, but the task was complicated in a country so big and populous.

"The militants are able to exploit certain things on the ground, like the anti-American sentiment, which is not just in society -- it's also in the military," he added.

In the Taliban-riddled northwest, meanwhile, a homicide car bomb exploded next to a police station in the Saddar area of Kohat, collapsing half the building and killing 11 people -- three police officers and eight civilians -- Kohat police chief Abdullah Khan said.

Early Thursday evening, a bomb exploded in a car outside a housing complex for government employees in the northwestern city of Peshawar, killing a 6-year-old boy and wounding nine others, most of them women and children, said Liaqat Ali Khan, the top police official in the region. He said an assailant parked the car outside the house and walked away before remotely detonating the bomb.

The U.S. has encouraged Pakistan to take strong action against insurgents who are using its soil as a base for attacks in Afghanistan, where U.S. troops are bogged down in an increasingly difficult war. It has carried out a slew of its own missile strikes in Pakistan's lawless tribal belt over the past year, killing several top militants.

One suspected U.S. missile strike killed four people overnight Thursday when it hit a compound in an area in North Waziristan tribal region where members of the militant network led by Jalaluddin Haqqani are believed to operate, two intelligence officials said. They spoke on condition of anonymity because they were not authorized to speak to the media.

Pakistan formally protests the missile strikes as violations of its sovereignty, but many analysts believe it has a secret deal with the U.S. allowing them.

The Taliban have claimed credit for a wave of attacks that began with an Oct. 5 strike on the U.N. food agency in Islamabad and included a siege of the army's headquarters in the garrison city of Rawalpindi that left 23 people dead.

The Taliban have warned Pakistan to stop pursuing them in military operations.

The Pakistani army has given no time frame for its expected offensive in South Waziristan tribal region, but has reportedly already sent two divisions totaling 28,000 men and blockaded the area.

Fearing the looming offensive, about 200,000 people have fled South Waziristan since August, moving in with relatives or renting homes in the Tank and Dera Ismail Khan areas, a local government official said, speaking on condition of anonymity because he was not authorized to talk to the media.

The Associated Press contributed to this report.