Paramilitary soldiers conducting a major operation in northwestern Pakistan engaged Taliban militants in fierce fighting that killed 10 soldiers and at least three dozen insurgents today, AP quoted officials as saying. The clashes took place in Bajur, a tribal area where the military has twice declared victory following big offensives but attacks blamed on militants continue. The persistent violence illustrates how difficult it is to pacify Pakistan's rugged Afghan border area. The paramilitary Frontier Corps faced heavy resistance during the operation and several of their vehicles were ambushed as they tried to deliver reinforcements, said a military official, speaking on condition of anonymity because he was not authorized to talk to the media. The fighting occurred in two different areas near the main town of Khar, and soldiers eventually called in helicopter gunships to pound militant positions after battling the insurgents for hours, said Iqbal Khattak, Bajur's deputy administrator. Both Khattak and the military official said 10 soldiers died in the fighting, but they differed on the number of militants killed. Khattak said 36 were killed, while the military official put the number at 43. Twelve soldiers were wounded in the fighting and 23 militants were arrested, said the military official. The military first declared victory in Bajur following a six-month operation launched in late 2008. But the army was forced to launch a follow-up operation in late January this year and declared victory again about a month later.