One person was taken to the hospital after escaping a second floor window during a fire at a Fond du Lac duplex.Firefighters say they were called after 11 p.m. to the 200 block of Packer Street.Crews brought the fire under control within 45 minutes, but the duplex had heavy fire, smoke and water damage.Firefighters say a nearby garage and vehicle were also damaged.Investigators are working to determine how the fire started.