US Air Force B-52 bomber crashes in flames in California, killing all 8 crew aboard

 A U.S. Air Force B-52 Stratofortress bomber crashed on takeoff on Monday at Edwards Air Force Base in ‌Southern California's Mojave Desert, bursting into flames and killing all eight crew members aboard, Air Force officials said.

The eight-engine, jet-powered aircraft, built to carry a wide array of nuclear and conventional bombs, was on a routine test mission when it crashed on the runway at Edwards just after leaving the ground, Air Force Colonel James Hayes said ​at a press conference hours later.

A towering pall of black smoke billowing from the crash site was visible for miles immediately ​after the accident.

He said the "mixed crew" aboard the aircraft consisted of government civilians, government contractors and uniformed military personnel. ⁠Aerospace giant Boeing (BA.N), opens new tab, which designed and built the plane, said two of its employees were among the dead.

The flight was intended to support ​a radar modernization program, Hayes told reporters. The cause of the crash was unknown and under investigation, he added.

Air Force officials did not name the ​victims, saying they were still in the process of notifying their next of kin.

Aerial video footage of the crash scene, about 100 miles (161 km) north of Los Angeles, showed a charred, smoldering patch of the desert floor larger than a football field as an emergency vehicle was seen driving along the site's perimeter. From a distance, ​there were no large pieces of debris readily visible in the footage.

Hayes said the crash was quickly "deemed to be unsurvivable."