The violence comes as Pakistan and the U.S. appear to have made gains in the battle against al-Qaida and the Taliban. Officials confirmed earlier in the week that the No. 2 Afghan Taliban leader, Mullah Abdul Ghani Baradar, was arrested days before in the southern Pakistani city of Karachi, and that several other Taliban and al-Qaida-linked militants were captured in a crackdown.
The suicide attacks Saturday began within minutes of each other in Mansehra district, police official Gul Zareen said.
Local police chief Khalil Khan died and two officers and two passers-by were wounded when one attacker blew himself up inside the police station in Mansehra town, he said. A second suspect fled the scene.
In the second attack, two people stormed a police station about 15 miles (25 kilometers) away in the town of Balakot, triggering a shootout that left one attacker dead. Two officers were wounded, while the second attacker fled toward nearby offices.
Islamist militants in Pakistan frequently attack the country's security forces, and are also suspected of being involved in attacks on NATO and U.S. troops across the border in Afghanistan.
However, such assaults are relatively rare in Mansehra, about 90 miles (140 kilometers) northwest of the capital, Islamabad. Pakistan dismantled militant training facilities there after the Sept. 11, 2001, attacks in the United States.
Other large swathes of Pakistan's northwest have become militant strongholds, and in some places, the Pakistani military has been waging offensives to push the extremists out.
An army statement said an airstrike Saturday hit a militant hide-out in the Shawal mountains of the South Waziristan tribal region after a tip-off that insurgents were hiding there. It said 30 militants were killed but provided no further details.
The military has been trying to clear South Waziristan of Pakistani Taliban fighters since October. The region is remote, dangerous and largely restricted to outsiders, making independent confirmation of the army's statement nearly impossible.