ST. PAUL  (AP) - The number of people killed while riding motorcycles in Minnesota has risen significantly this year.

Forty-seven motorcyclists have died in 2012, including five people in the past seven days. Most recently, a motorcyclist died after he hit a slow-moving farm tractor between Sauk Rapids and Rice Wednesday. The number of fatalities this year has surpassed 42 deaths in all of last year.

Department of Public Safety officials say the perennial factors in motorcycle deaths are alcohol use, rider error and failure to yield.   Experts say this year's rise in fatalities could be attributed to having more riders on the roads as well as a warm spring that brought bikers out sooner.

(Copyright 2012 by The Associated Press. All Rights Reserved)