COTTAGE GROVE, Wis. -

Police said a 44-year-old man died in a crash Thursday morning in Cottage Grove. A second crash occurred 17 minutes later involving cars stopped in traffic due to the fatal accident, injuring three more people. 

The Cottage Grove Police Department said officers responded to a report of an accident on Highway N north of Natvig Road at 8:09 a.m.

The 44-year-old Cottage Grove man was southbound on Highway N when his car crossed the center line and struck a northbound semi, according to the report. The semi and car both came to rest in the west ditch. 

Police Chief Chris Hughes said investigators have not determined why the Cottage Grove man's car crossed the centerline. 

The area where the crash occurred is level and flat, but the centerline was covered with snow, he said. 

Alcohol and drugs are not believed to be a factor, Hughes said. 

Police said the semi driver was not injured. 

At 8:26 a.m., a three-car pileup was reported just north of the fatal accident, police said. 

A 64-year-old Cottage Grove woman's vehicle collided with two cars stopped due to the initial crash, Hughes said. Her vehicle hit a car driven by a 59-year-old Cottage Grove woman, which caused that vehicle to strike a vehicle driven by a 59-year-old Sun Prairie man. 

Police said three people suffered non-life-threatening injuries. Only the 64-year-old woman was taken to a local hospital. 

Highway N was closed due to the fatal crash for more than 4 hours but reopened at about 12:30 p.m.

Police withheld the name of the man killed in the first accident pending notification of his family. 

The fatal accident remains under investigation, police said. 

Highway N and Highway 12 EB