WASHINGTON, Aug. 9, 2011 -- President Barack Obama traveled to Dover Air Force Base, Del., today for the return of 30 U.S. servicemembers killed in a helicopter crash in Afghanistan on Saturday.

Thirty International Security Assistance Force members, one civilian interpreter, and seven Afghan commandos were killed when a coalition CH-47 Chinook crashed in Afghanistan early Aug. 6.

All of the ISAF servicemembers on board were from the United States, officials said. They added that the incident represents the highest number of U.S. forces killed during a single event in support of Operation Enduring Freedom.

The dead servicemen included a number of Navy SEALs, officials said. Some of them were reportedly from SEAL Team 6, the unit that carried out the raid on Osama Bin Laden.

The Chinook helicopter crashed in the rugged and remote Tangi valley of Eastern Afghanistan. U.S. officials have said the crash may have been caused by insurgents firing a rocket-propelled grenade, but emphasized that an investigation is underway to determine the exact cause.

“No words describe the sorrow we feel in the wake of this tragic loss,” said Gen. John R. Allen, commander, International Security Assistance Force. “All of those killed in this operation were true heroes who had already given so much in the defense of freedom. Their sacrifice will not be forgotten. Our thoughts and prayers are with the families who are now waiting for their loved ones to return home. We will do everything in our power to support them in this time of need.”

“We also mourn the loss of our heroic Afghan partners who fight with us shoulder to shoulder, every day,” added Allen.

(Information taken from an ISAF news release and a White House Office of Communications pool report.)