Another Starship prototype exploded Tuesday morning during an attempt to nail a tricky landing technique at SpaceX’s test launch facilities in Texas. The landing attempt followed a clean liftoff and a demonstration of the rocket’s autonomous in-flight maneuvers, marking SpaceX’s fourth high-altitude flight since December.

The SN11 rocket launched at 9AM ET in foggy weather at SpaceX’s Boca Chica, Texas facilities, soaring roughly 6.2 miles to test the rocket’s three Raptor engines and a number of in-flight maneuvers that steer it back to land. As SN11 neared peak altitude, the engines gradually shut down to begin its free-fall back toward the ground before executing a “landing burn” — when one Raptor reignites to carry the rocket gently down to a landing pad not far from where it launched. At least, that’s the idea.

“Something significant happened shortly after landing burn start,” SpaceX CEO Elon Musk tweeted shortly after the explosion. “Should know what it was once we can examine the bits later today.”

A live camera feed aboard SN11, streamed by SpaceX, froze moments before its landing attempt. Another feed, provided by the website NASA Spaceflight, showed large chunks of debris raining on SpaceX’s Boca Chica facilities, though the landing explosion itself was obscured by fog.

“Looks like we had another exciting test,” SpaceX’s John Insprucker said on SpaceX’s live stream, suggesting the vehicle was lost in another eventful landing attempt. “We do appear to have lost all the data from the vehicle, and the team of course is away from the landing pad.”

“At least the crater is in the right place!,” Musk tweeted. One of SN11’s engines “had issues” during ascent and didn’t fire strongly enough during the landing burn, he said.

While the fog ruined views of SN11’s landing attempt, a weather radar from the National Weather Service in Brownsville, Texas detected a plume of gas that indicated an explosion in mid-air.

Developing…