St. Paul, MN  (KROC-AM News) - There have already been 11 motorcycle-related traffic fatalities in Minnesota this year.

The State Department of Public Safety says that is the highest number of motorcycle rider deaths this early in the season in at least 21 years. The state only began tracking statistic in 1994.

An advisory issued by the department on Thursday notes four of the motorcycle-related traffic deaths are the result of separate crashes that occurred over a four-day period beginning last Saturday. It also notes three of the victims were wearing helmets and only one of the fatal crashes involved another vehicle.

Overall, Minnesota has experienced 106 traffic fatalities this year, which means motorcycle crashes account for about 10-percent of the 2015 death toll.

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