A Detroit freeway pileup left two children and an adult dead Thursday. The pileup was caused by severe wind and snow, leading to a mile-long stretch of car crashes that shut down the highway for hours, authorities said.

A series of crashes on Interstate 75 led to the massive pileup of some 30 vehicles, reports The Associated Press. Thirteen people were transported to hospitals while several others were treated at the scene. SUVs, tractor-trailers and hybrids could be seen smashed on the highway in the pileup, which occurred around the Rouge River Bridge around 9:30 a.m., reports The Detroit News.

Michigan State Police Lt. Michael Shaw said a 7-year-old boy died at the scene while his 9-year-old sister died in the hospital, reports AP. Their parents were also hurt in the crash, according to The Detroit News. The family was from Windsor, Ontario, Canada.

Snow and wind combined to form whiteout conditions that led to several other major traffic accidents across Michigan Thursday, including two other pileups, in Genesee and Van Buren counties, reports The Detroit News. The Salvation Army sent food and blankets to I-75 victims, while a warming bus also helped those trapped on the highway to have some measure of comfort.

The roads around the Rouge River Bridge are especially dangerous in the winter. “We pay a lot of attention to the area of the Rouge Bridge because bridges and overpasses ice up quicker than the roadways,” a Wayne County spokeswoman told The Detroit News.  The whiteout seemingly came out of nowhere; Shaw said it went from, “clear to total whiteout in a matter of seconds,” reports AP.

A video of the Detroit pileup aftermath can be viewed below.