MOSCOW, October 18 (RIA Novosti) - Pakistani soldiers have killed 60 militants since the start of a large-scale ground operation against the Taliban in South Waziristan, the country's armed forces said Sunday.

The Pakistani forces have lost six servicemen and 12 have been wounded in the battle near the Afghan border that started on Saturday and reportedly involves about 28,000 Pakistani soldiers and some 10,000 Taliban militants.

The assault against the Pakistan-based Taliban, led by Hakimullah Mehsud, comes after days of militant violence across the country, in which up to 150 people have died.

The United Nations said on Friday that some 250,000 residents had fled the area ahead of the offensive. Refugee numbers are expected to rise as the fighting continues.

The attack has been expected since June 15, when the governor of the North West Frontier Province announced a ground offensive.

U.S. President Barack Obama signed legislation on Thursday providing Pakistan with $7.5 billion in aid over the next five years. Some of the funds are conditional on Pakistan fighting Taliban militants.