AUSTIN (KXAN) — Both decks of southbound Interstate 35 are open starting near East 51st Street following a deadly semi-truck crash that closed the upper and lower decks Thursday morning.

APD says they got the call at 1 a.m. Thursday morning. The driver hit the guardrail of the upper deck, and then the cab split from the trailer and fell to the lower deck, police say. The trailer stayed on the upper deck. This crash happened right where the upper and lower deck split, so this was not a significant distance between where the cab and trailer ended up.

Police aren’t sure why the truck driver lost control of the semi-truck, and they say it was the only vehicle involved in the crash. The driver died at the scene.

The portion of the freeway was closed until around 12 p.m. Hazmat crews cleaned up the fuel spill caused by the crash.

“That fuel spill came down through the drainage areas and on to the surface frontage road down below,” Sgt. Robert Barger said. “APD responded to that, determined that the spill after doing some mitigation, determined that the spill required a hazmat response. That’s ongoing.”