The death of a man in Chicago's Humboldt Park neighborhood, the fourth fatality to fire since Monday, prompted firefighters to hit the streets to hand out smoke detectors and advice on fire safety.
The American Red Cross of Greater Chicago said it has responded to 19 house fires since early Monday morning.
The latest fire, in the 900 block of North Keystone Avenue, claimed the life of 24-year-old Felix Salva and at least two dogs. Another dog was rescued.
Most of Salva's family was in Puerto Rico at the time of the fire attending a funeral.
While the cause of the fire is undetermined, investigators said signs are pointing to the Christmas tree.
The fatalities this week bring the number of fire deaths for 2008 to 18. Still too many, authorities said it's the lowest number in modern history of the city.
There were 32 fire deaths in 2007 and 43 in 2006. In late 1970s and early 1980s, there were more than 100 deaths per year.