KALAMAZOO, Mich. (WOOD) — Several people sustained minor injuries when a school bus and other cars were hit by pieces of concrete on I-94 in metro Kalamazoo.

The reports came in around 12:30 a.m. Sunday from the westbound lanes of the highway near Sprinkle Road, the Portage Department of Public Safety said. Police say a school bus, semi-truck and at least one passenger car were damaged and pulled over. The drivers said pieces of concrete had hit their windshields.

Some of the people on the bus sustained minor injuries and were treated at the scene. There were no serious injuries.

Battle Creek resident Sarah Stimac said her side window and passenger’s side door were damaged, but it could have been worse.

“My husband had actually just rolled his window because it was all the way down, so if he would not have rolled up his window and left it just cracked, it’s hard telling what would’ve happened,” she said.

There is construction in the area of the reports, but Portage Public Safety Director Nicholas Armold said he thinks the concrete may have been thrown by someone.

“The potential is that something fell from the overpass but that’s probably highly unlikely,” Armold said.

He said throwing objects at moving vehicles can be deadly.

“Whether or not they’re actually struck and killed or the impact causes a crash where they’re later severely injured or die,” he said.

Officers looked around the construction areas around the Sprinkle and Portage Road overpasses but didn’t find anyone who may have thrown the concrete.

Stimac said if it was thrown, she hopes the person responsible is held accountable.

“This is dangerous,” Stimac said. “This is not something that should be brushed off. It’s serious.”

Anyone with information about what happened is asked to call Portage police at 269.329.4567 or Silent Observer at 269.343.2100.