ASADABAD, Afghanistan — American and Afghan troops have killed at least 115 insurgents as part of a tough fight to gain control of a critical corridor and resupply route to a key American base in northeastern Afghanistan, according to Afghan and American military officers.

Civilians in the area, as well as American and Afghan soldiers, described an exceptionally intense fight, which was still going on, in which long-range bombers have flown in from as far away as the Persian Gulf emirate of Qatar, the southern Afghan province of Kandahar and Bagram Air Base outside Kabul, the Afghan capital.

The Americans have also fired long-range rockets from more than 100 miles away as the troops have struggled to oust large numbers of insurgents who month after month have attacked convoys on the road and dominated much of this corner of Kunar Province.

“We had too many F16s and F15s to count, almost continuous coverage,” said Capt. Ron Hopkins, 27, the fire support officer of the Second Battalion, 27th Infantry Regiment, who was in the command center for the fight.