Pakistani soldiers killed 12 militants in gunbattles over the past day, officials said Saturday, as government forces pressed on with their offensive in the mountainous Taliban sanctuary of South Waziristan.

The military said that while the army has taken control of two former strongholds — Sararogha and Ladha — there were still occasional clashes with militants. The army was still battling for full control of Makeen, which they call the "nerve center" of the Pakistani Taliban.

The fighting left a total of 12 militants dead and five Pakistani soldiers injured over the past 24 hours, the military said in a statement, adding that large numbers of weapons and ammunition had been found, some hidden in deep tunnels dug in the hills.

"The fight against militancy ... is a long and tough battle as we have to not only fight the extremists but also the extremist mindset," President Asif Ali Zardari told a group of lawmakers Friday night, according to his spokesman. "The adversary in this battle should not be underestimated."

In mid-October, Pakistan launched an offensive in South Waziristan, a semiautonomous tribal region along the Afghan border where the government has seldom had significant influence, and which has become the main Taliban and Al Qaeda sanctuary in the country. The military says hundreds of militants have been killed in the fighting — a claim the Taliban dismisses.

The reality of the situation remains unclear. While refugees fleeing the area have reported fierce fighting, there have been few specific details. Journalists are not allowed into the region except on carefully orchestrated government trips.

The offensive has sparked a wave of retaliatory attacks across Pakistan.