No one was injured in the crash about 3:40 a.m. Friday along eastbound Interstate 94 in Burns Harbor. All eastbound lanes reopened by noon.
Indiana State Police say a truck driven by 70-year-old Radmilo Samardzio of Ballwin, Missouri, pulled over with its hazard lights on so he could get a bottle of water when it was struck by one driven by 57-year-old Steven S. Dare of Hudsonville, Michigan.
Police say a preliminary investigation found Dare reached for something, causing the truck to drift.
Samardzio was hauling food products including cocoa powder. Dare had merchandise that included roughly 100 pounds (45 kilograms) of lithium batteries. Police say some batteries leaked, briefly causing small fires.