WASHINGTON (AP) - U.S. officials say none of the Navy SEALs who died in a helicopter crash in Afghanistan had participated in the raid that killed Osama bin Laden, although they were from the same unit that carried out the bin Laden mission.

More than 20 Navy SEALs were among those lost in the crash in Afghanistan.

The operators from SEAL Team Six were flown by a regular Army crew. That's according to AP military sources.

The team included 22 SEALs, three Air Force air controllers, seven Afghan Army troops, a dog and his handler, and a civilian interpreter, plus the helicopter crew.

It's the largest single loss of life ever for SEAL Team Six, known as the Naval Special Warfare Development Group.

All sources spoke on condition of anonymity to discuss sensitive military matters.

President Hamid Karzai sent his condolences to President Barack Obama, according to a statement issued by his office.

The Taliban claims to have brought the helicopter down with a rocket attack, but they have been known to make exaggerated claims in the past.

NATO says there "was enemy activity in the area."

Saturday, the US Department of Defense released the following statement.

"I am deeply saddened by the loss of many outstanding Americans in uniform and of their Afghan counterparts earlier today in Afghanistan. Their courage was exemplary, as was their determination to make this a safer world for their countries and for their fellow citizens. We will stay the course to complete that mission, for which they and all who have served and lost their lives in Afghanistan have made the ultimate sacrifice. They and their families are in my thoughts, in my prayers and in my heart."

(Copyright 2011 by The Associated Press. All Rights Reserved.)