Pakistan officials say militants in the restive northwest tribal region have killed six men after accusing them of spying for the U.S.

Authorities said Sunday five of the men were found on the outskirts of Miran Shah, the main town of North Waziristan.  Officials say a sixth body was found in another town, also near Miran Shah.  

Police say notes accusing the men of working as U.S. spies were found on the bodies in both locations.

On Saturday, Pakistani officials said fighting between security forces and the Taliban in the northwest killed 22 militants and two soldiers.

Authorities say one gunbattle began when militants attacked a security checkpoint in the Orakzai tribal region.  Elsewhere, government artillery fired on insurgent positions in the neighboring Kurram district, bordering Afghanistan.

Also Saturday, a suicide bomber rammed a car with explosives into a police station in Tank, a district bordering South Waziristan, killing two policemen and two civilians and wounding at least nine others.  

In other violence, militants attacked a fuel tanker outside the northwestern city of Peshawar.  Police say the attackers ordered the driver and his assistant to leave the vehicle and then set it on fire.

Militants in Pakistan frequently attack tankers and trucks carrying supplies to U.S. and NATO-led forces battling the Taliban in Afghanistan.

Some information for this report was provided by AP, AFP and Reuters.