NATO aircraft have killed more than 60 suspected insurgents over the last several days in an increasingly volatile southern Afghan province, the military alliance said Sunday.

Afghanistan's Ministry of Defense said 40 Taliban fighters were killed by NATO airstrikes in Helmand that "completely destroyed" a militant base in the district of Grishk on Saturday. Maj. Luke Knittig, a NATO spokesman, said the alliance also estimated that about 40 fighters were killed.

A NATO helicopter, meanwhile, fired on about 20 insurgents who had attacked a NATO patrol in neighboring Naw Zad district on Friday, killing 15 of the suspected insurgents, the alliance said.

CountryWatch: Afghanistan

In a third incident, an attack helicopter fired on a group of insurgents who shot at a support helicopter on Thursday, killing eight of the militants in nearby Sangin district, the statement said. There were no NATO casualties in the attacks.

Southern Afghanistan over the last several months has seen some of the fiercest fighting since the U.S.-led invasion in 2001 toppled the Taliban regime.

NATO troops, mostly from Canada and Britain, moved into the region earlier this summer.

Britain's Prime Minister Tony Blair, whose country has about 5,000 troops in southern Helmand province, said that NATO's battle with Afghan insurgents has been more difficult than anticipated but must continue.

"I think the particular mission was tougher than anyone expected. But I'm not surprised it was tough," Blair said in an interview with the British Broadcasting Corp.

"The whole reason we've gone into that as part of the NATO force under the U.N. resolution is because it is essential for the Taliban and Al Qaeda to come back into the southern part of Afghanistan and it's essential for us to keep them out," Blair said.

Blair's government has had to cope with charges by middle-ranking officers in Afghanistan that ground troops have not received adequate air support and other backing.

Adm. Edmund P. Giambastiani Jr., vice chairman of the U.S. Joint Chiefs of Staff, on a visit to Afghanistan earlier this month, said the U.S. military was better able to detect roadside bombs before they detonate thanks in part to the launch of a dedicated anti-explosives military team.

"Now we must work harder every day toward reducing our numbers of causalities from these horrible attacks," said Giambastiani, according to statements the U.S. military released Sunday.

Taliban fighters have increasingly used suicide and roadside bomb attacks against Western troops and civilians.

The anti-explosives team focuses on trends, techniques, tactics and procedures used in developing the devices, and that information is passed on to troops in the field, the statements said.

Giambastiani said the U.S. Navy and Air Force are sending electronic warfare officers to Afghanistan and Iraq to work on counter-explosives measures. He said the military planned to purchase route-clearing equipment such as heavy-duty tactical vehicles in both Iraq and Afghanistan.

NATO currently has about 20,000 troops in Afghanistan, while the United States has another 21,000, mostly in the eastern part of the country along the border with Pakistan.