Blue Origin’s New Glenn rocket exploded in a massive fireball while undergoing a test on a Florida launchpad Thursday evening, dealing a major setback to the Jeff Bezos-backed firm in its efforts to challenge a dominant SpaceX.

A Blue Origin New Glenn rocket has dramatically exploded on the launchpad during a test, in a setback for Jeff Bezos’ space venture as it seeks to narrow the gap with Elon Musk’s SpaceX.

“We experienced an anomaly during today’s hotfire test,” Blue Origin tweeted Thursday night.