Pakistani fighter jets and attack helicopters bombarded militant hideouts in the northwest Swat valley on Monday, intensifying an offensive around a key Taliban stronghold, officials said. The military said troops were closing in on Mingora, the capital of Swat and under Taliban control, as part of a punishing anti-militant offensive, which the United Nations said displaced more than 1.1 million people in two weeks. "Fighter jets and helicopter gunships targeted hideouts of Taliban militants in Peochar and Takhta Bund areas in Swat on Monday morning," a military official said on condition of anonymity. Another security official confirmed shelling against suspected militant hideouts in the two areas and described Takhta Bund as the main supply route for Taliban holed up in Mingora. Pakistani authorities say more than 1,000 militants and 45 soldiers have been killed in a three-pronged onslaught launched in the northwest districts of Lower Dir on April 26, Buner on April 28 and Swat on May 8. The military says up to 15,000 troops were taking on about 4,000 well-armed fighters in Swat, where Islamabad has ordered a battle to "eliminate" Islamist militants, branded by Washington the greatest terror threat to the West. Islamabad ordered the offensive under mounting US pressure after Islamist fighters took up positions just 100 kilometres (60 miles) from the Pakistani capital, having broken out of their hub in Swat.