PEWAUKEE, Wis. (CBS 58) -- An investigation is underway after a crash involving four vehicles left several injured in the city of Pewaukee Monday, Oct. 13.

According to the Waukesha County Sheriff's Department, four people were transported for treatment, with injuries ranging from minor to critical. 

Officials say multiple 911 calls were placed around 5 p.m. reporting the crash on eastbound I-94 at Pewaukee Road. 

Eastbound I-94 was fully closed at the eastbound Highway 16 interchange until around 6:30 p.m. 

The cause of the crash remains under investigation.