CHICAGO (CBS) — Two women were killed in a crash involving a Cook County Sheriff’s squad car Thursday morning in north suburban Niles. The officer suffered minor injuries

Niles police said a Cook County Sheriff’s squad car was headed east on Dempster Street around 5:45 a.m., when it struck the passenger side of a Honda Accord heading south on Harlem Avenue.

First responders had to pull two women out of the Honda. The driver, 69-year-old Ludwika Moskal from Norridge, and the passenger, 64-year-old Helena Lukasik from Chicago, were taken to Advocate Lutheran General Hospital, where they were pronounced dead.

A 47-year-old sheriff’s officer also was taken to Lutheran General, but his injuries were not life-threatening. The officer was not responding to a call at the time, but the sheriff’s office said he was on duty.

The Major Crash Assistance Team from the North Regional Major Crimes Task Force was investigating the cause of the crash.

Police said they believe weather is partly to blame.

“We believe that the rain or the slick roadways were a factor in the accident,” Niles Police Cmdr. Robert Tornabene said.

Tornabene said Dempster and Harlem is a busy intersection any time of day.

“You do get a lot of early morning traffic, and construction workers and workers going into work; families coming home or workers coming home at night from their night jobs. So, yeah, it’s a busy intersection,” he said.

The intersection was closed for about five hours after the crash as officers investigated.