The B-1B bomber cited in a bombing attack that killed civilians in Afghanistan last month is based at Dyess Air Force Base in Texas, not Ellsworth AFB, the Ellsworth Public Affairs office said this week.

The B-1 crew failed to follow all operational rules in a complex battle in Afghanistan on May 4 that killed about 26 civilians and 78 Taliban fighters, the U.S. military concluded in a report released Friday. That report did not specify whether the B-1 was from Dyess or Ellsworth.

About two-thirds of the operational B-1s in the Air Force are based at Ellsworth, with the remainder at Dyess.

The B-1 has been a workhorse in close air support of ground troops in the wars in Iraq and Afghanistan.

No B-1s from Ellsworth are deployed in either theater, according to Ellsworth Public Affairs. But more than 250 Ellsworth personnel are deployed worldwide, most of them in support of the Iraq and Afghanistan wars, base officials said.

Friday's report said two of three strikes by the Dyess B-1 near the close of a chaotic firefight in the western Farah Province probably accounted for the civilian deaths.

The report contained only mild criticism of the B-1 bomber crew involved, and Defense Secretary Robert Gates earlier said there was no reason to punish any U.S. personnel. The B-1 bombed the targets in coordination with friendly forces on the ground, the report said.

Unintended civilian casualties in the war in Afghanistan have become a troublesome issue for the Afghan government and for Coalition forces.

The report recommends refining the current rules for operations.

Part of Ellsworth's standard training for B-1 crews before deployment includes live and simulated munitions training at ranges in the United States, according to Col. Jeffrey Taliaferro, 28th Bomb Wing commander at Ellsworth.

"Aircrews here communicate with aircrews downrange to refine their situational awareness of the battle space, and our training here remains centered on meeting the downrange commander's intent to provide for the security of the Afghan people and minimize civilian casualties," Taliaferro said in an e-mail to the Journal.

Contact Steve Miller at 394-8415 or steve.miller@rapidcityjournal.com.