ISLAMABAD , Pakistan ( CNN ) -- Pakistani soldiers and militants battled Saturday in the country 's vast tribal region , with more than a dozen insurgents killed in airstrikes , at least four soldiers slain in skirmishes and a key village seized by troops , the military said . A Pakistani soldier pictured during operations against militants in June . The fatalities come hours after Pakistani troops launched a massive ground offensive backed up by air power targeting the Taliban in South Waziristan , a refuge and a power base for insurgents operating in Pakistan and along the Pakistani-Afghan border . The highly anticipated offensive , which comes after a wave of suicide attacks in Pakistan , also has prompted the exodus of tens of thousands of civilians , the U.N. refugee agency said . One military official said Pakistani troops seized control of Kotkai , where Pakistani Taliban leader Hakimullah Mehsud has lived with fellow commander Qari Hussein , the mastermind behind some of Pakistan 's deadliest suicide attacks . Watch how the offensive began » . Another military official said the airstrikes from jet fighters and helicopter gunships targeted militant hideouts in Kotkai and the villages of Badar , Barwand and Khisur , all strongholds of the Taliban and their late leader Baitullah Mehsud . The official asked not to be identified because he is not authorized to speak to the media . There have been confrontations throughout the day between soldiers and militants . Along with the four slain soldiers , 12 have been wounded , the military said . Gen. Athar Abbas , the Pakistan military spokesman , said the ground offensive in South Waziristan was launched shortly after midnight after the military received clearance from the government . He said the region 's eight entry and exit points have been sealed by troops . Pakistani officials say that about 10,000 to 15,000 militants linked to the Taliban or to al Qaeda operate in South Waziristan , a harsh terrain familiar to militants but difficult for others to navigate . About 28,000 Pakistani soldiers have moved into the epicenter of Taliban activity in the region to counter their activities , officials said . Elsewhere in Pakistan 's tribal region , in the Mohmand Agency , at least eight militants and one soldier were killed Saturday when they exchanged gunfire near a military checkpoint , the military said . For months , the military had been targeting militant hideouts in South Waziristan and other hot spots in Pakistan 's tribal areas . This year , troops launched a large operation targeting militants in the Swat Valley , in Pakistan 's North West Frontier Province . But despite these efforts , insurgents have continued to strike with relative impunity inside Pakistan , brazenly targeting government , police and security locations . The latest attack occurred Friday in the northern city of Peshawar , when a suicide car bomber detonated near a police station , killing 13 people , most of them civilians . The recent wave of deadly attacks has raised concerns about the ability of Pakistan 's security forces to maintain control . The attacks heightened internal and international pressure on the government to take swift and effective action . In a high-level meeting Friday , army chief Gen. Ashfaq Kayani `` gave a detailed briefing on the prevailing national security situation and its ramifications in the future , '' according to a statement from the prime minister 's office . Those who attended the meeting condemned the recent attacks and `` agreed that these elements pose a serious threat to the sovereignty and integrity of the state , '' the statement said . The attacks show `` once again that the militants in Pakistan threaten both Pakistan and the United States , '' White House Deputy Press Secretary Bill Burton said . On Thursday , President Obama approved an additional $ 7.5 billion in assistance to Pakistan over the next five years .
NEW : Official says troops take village of Kotkai . About 28,000 Pakistani soldiers move into epicenter of Taliban activity . Up to 10,000 militants operating in South Waziristan , officials estimate . Tens of thousands of civilians fleeing region , U.N. refugee agency says .