At least 45 Taliban fighters and four security personnel were killed when Pakistani troops repelled an overnight attack by militants on a paramilitary camp in the troubled South Waziristan tribal region, officials said on Sunday.

The attack on the security forces' camp near the border with Afghanistan sparked a gun battle that lasted for eight hours, officials were quoted as saying by television news channels. The officials said 45 militants and four security personnel were killed in the skirmish. However, Geo News channel has put the number of militants killed at 50. Security forces have also started an offensive in different areas of Spinkai Raghzai, Officials in the political administration of South Waziristan Agency said.

The offensive was launched following several attacks on the security forces. The Taliban have stepped up their activities in South Waziristan, a stronghold of militant commander Baitullah Mehsud, following operations against them in Buner, Dir and Swat districts of the North West Frontier Province.

The Pakistan Army has claimed it has killed hundreds of militants in Malakand division, which includes Swat, and captured Mingora, the main city in the region.

Meanwhile, security forces arrested six militants associated with the Tehrik-e-Taliban Pakistan from an area near Landi Kotal in Khyber Agency and recovered a large number of arms from them. The militants were arrested during a search operation. Three assault rifles, an anti-aircraft gun, two rockets, wireless equipment and mobile phone sets were seized from them.