WASHINGTON  The deaths of seven Central Intelligence Agency operatives at a remote base in the mountains of Afghanistan are a pointed example of the civilian spy agency’s transformation in recent years into a paramilitary organization at the vanguard of America’s far-flung wars.

Even as the C.I.A. expands its role in Afghanistan, it is also playing a greater role in quasi-military operations elsewhere, using drone aircraft to launch a steady barrage of missile strikes in Pakistan and sending more operatives to Yemen to assist local officials in their attempts to roll back Al Qaeda’s momentum in that country.

The C.I.A. operatives stationed at Forward Operating Base Chapman in Khost Province, where Wednesday’s suicide bombing occurred, were responsible for collecting information about militant networks in Afghanistan and Pakistan and plotting missions to kill the networks’ top leaders. In recent months, American officials said, C.I.A. officers at the base had begun an aggressive campaign against a radical group run by Sirajuddin Haqqani, which has claimed responsibility for the deaths of dozens of American troops.

Over the past year, the C.I.A. has built up an archipelago of firebases in southern and eastern Afghanistan, moving agency operatives out of the embassy in Kabul and closer to their targets.