SpaceX’s massive Starship rocket exploded minutes after it cleared the launch pad during a flight test Thursday. Elon Musk had said the test posed steep challenges and risks.

SpaceX’s futuristic Starship looked like it aced a touchdown in South Texas Wednesday, but then exploded on the landing pad with so much force that it was hurled into the air. SpaceX did not immediately say what went wrong on the March 2021 landing in Texas.