(CNN) -- A suicide bomb detonated Thursday inside a mosque in violence-wracked northwestern Pakistan, killing at least 12 people, including children and soldiers, and wounding 25, military officials said.
A policeman stands in front of a damaged vehicle at a suicide blast site Thursday in Hub, Pakistan.
The attack happened in Kohat, outside Peshawar in the North West Frontier province.
Earlier attacks around Pakistan killed at least 35 people and wounded 47 Thursday -- adding to the recent surge in violence wracking Pakistan, authorities said.
Violence has increased in northwestern Pakistan since a bloody siege at Islamabad's Red Mosque -- which ended last week -- that pitted radical Islamists against Pakistan's military government forces. See images of Pakistani violence »
Earlier Thursday, a suicide bomber rammed an explosives-packed car into the gates of a police training center in Hangu -- 25 miles (40 kilometers) west of Kohat -- killing at least eight people and wounding 22, a police official said.
Also Thursday, in southern Pakistan, police said a bomb explosion near a bus stop killed at least 27 people and wounded 25 in Hub, a town in gas-rich Baluchistan province near the port city of Karachi.
The attack targeted Chinese engineers who were passing through the area, authorities said.
Since late last week, attacks targeting Pakistani security forces have killed more than 100 people, authorities said.
On Wednesday, the Pakistani army said at least 16 soldiers were killed when militants attacked an army convoy in North Waziristan, near the Afghan border. At least 10 others were wounded in the attack.
Tensions across the predominantly Muslim country -- flanked by its nuclear rival India on one side and war-torn Afghanistan on the other -- have been simmering.
The fresh wave of violence in Pakistan was triggered by the recent events at Islamabad's Red Mosque, where the military squared off with Islamic extremists holed up in the mosque. That event ended with a bloody military siege on the mosque, killing dozens of people in a weeklong standoff.
Adding to the tension, a suicide bomber on Tuesday attacked the site in Islamabad of a scheduled rally supporting the country's suspended chief justice and killed at least 12 people, sources said.
Hospital sources said that at least 35 others were wounded in the attack, which occurred where a rally was to be held for the Iftikhar Mohammed Chaudhry.
Pakistani President Pervez Musharraf removed Chaudhry from his post on March 9, accusing him of misusing his powers. The dismissal sparked widespread, largely peaceful demonstrations by the country's attorneys and those who believe Musharraf abused his authority in suspending Pakistan's top judge.
Militants linked to the Taliban in the area near the Afghan border have said the truce reached with the Pakistani government last September is off.
That deal has been blamed for an increase in attacks on U.S. troops over the border in Afghanistan, as Taliban fighters were able to prepare, train and rebuild weapons supplies without interference from the Pakistani government.
The Taliban is the former Afghan regime that sheltered al Qaeda until the U.S.-led war following the September 11, 2001, attacks.
Now, U.S. intelligence officials say al Qaeda has established a "safe haven" in Waziristan, just over the border in Pakistan -- and that Osama bin Laden is believed to be in the area.
The series of bombings in recent days in northwestern Pakistan, after the collapse of a truce between the government and tribal militants has been spreading fears in the region and the West.
U.S. officials have expressed concern over Pakistan's stability and effectiveness in suppressing terrorism.
Declassified portions of the National Intelligence Estimate released Tuesday reported that al Qaeda has "protected or regenerated key elements" of its capability to attack the United States while in this safe haven.
On Wednesday, a co-chairman of the Iraq Study Group said that U.S. forces should go into Pakistan to rout al Qaeda from the mountainous tribal region on the border with Afghanistan.
Former Rep. Lee Hamilton, who also was vice chairman of the 9/11 commission, said, "I am very concerned that you have a safe haven in Pakistan today where they [al Qaeda] can regroup, rethink, and get ready for more attacks." Watch Hamilton advocate U.S. action in Pakistan »
Under increased pressure to cap the spread of Taliban and al Qaeda militants in Pakistan's lawless tribal regions, Musharraf has vowed to "fight against extremism and terrorism no matter what province." E-mail to a friend
CNN's Syed Mohsin Naqvi, Kelli Arena and Pam Benson contributed to this report.