The aircraft had taken off from Edwards Air Force Base for a routine test mission when the accident occurred.

Following the crash, a thick plume of smoke was seen rising from the site and was visible from a considerable distance.

"Today, Edwards Air Force Base experienced a terrible tragedy, and we lost eight great Americans," Col. James Hayes was quoted as saying by the BBC.

Hayes said the crash was "totally contained" within the Edwards Air Force Base runway area, adding that the base has temporarily grounded operations following the incident.

The cause of the crash remains unknown.

According to Hayes, the investigation into the cause of the accident could take more than six months to complete.

In a separate statement posted on X, Edwards Air Force Base said: "A United States Air Force B-52 Stratofortress crashed shortly after takeoff on the Edwards airfield at 11:20 a.m."

California Governor Gavin Newsom expressed condolences over the loss of lives.

"My thoughts are with the victims, their families, and the entire Edwards Air Force Base community impacted by this tragic incident," he wrote on X.

According to the US Air Force website, the B-52H Stratofortress is a long-range heavy bomber capable of performing a wide range of missions.

US Representative Vince Fong described the incident as "heartbreaking."

Authorities have launched an investigation into the crash as officials work to determine what led to one of the deadliest incidents involving the iconic bomber in recent years.