Heavy winds blew dirt across Interstate 25 just south of Pueblo, creating a “brown out” that made it nearly impossible to see and set off crashes involving more than 30 vehicles, authorities said. The Colorado State Patrol said four people died and 29 people were taken to hospitals with injuries ranging from minor to severe.

Colorado State Patrol Maj. Brian Lyons said the dust was kicked up by the strong winds around 10 a.m. Tuesday, leading to the multi-vehicle collisions. Lyons said visibility was “next to nothing,” according to the patrol.

Authorities said there were crashes on both sides of the interstate. The patrol reported that the crash on the southbound side led only to property damage.

The patrol said the pileup included six semitrailers. It also involved a pickup hauling a trailer carrying 32 goats, with four of the animals dying, the patrol said.

Trooper Sherri Mendez, a patrol spokesperson, said the cause of the crashes about 2 miles (3.2 kilometers) from Pueblo was still being investigated. She said the lack of visibility would be considered as one of the factors, but others may also have been involved.

Mendez said the same strong winds that hit eastern Colorado on Tuesday were also blamed for fanning wildfires and causing flight delays at Denver’s airport. The report also said it snowed in the western part of the state, bringing moisture to the mountains.