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.