A US Air Force B-52 Stratofortress bomber crashed and burst into flames shortly after take-off during a routine test mission at Edwards Air Force Base in California's Mojave Desert, killing all eight people on board.

An official said an investigation could take up to six months and noted the B-52 in question was involved in a "radar modernization program."

Eight people were killed after a US Air Force B-52 bomber crashed shortly after take-off from Edwards Air Force Base in California's Mojave Desert on Monday.