It's been more than five weeks since an arsonist suspected in a series of fires in Ann Arbor has struck, investigators say.

Police say they currently don't have any suspects in the rash of fires, which date back to the beginning of the year and include numerous car and trash fires. The fires have primarily occurred in student housing areas near the University of Michigan's Central Campus.

U-M Department of Public Safety spokeswoman Diane Brown said no suspected arson fires have occurred since April 17, when four cars were set fire over a 20-minute span.

Firefighters work to put out one of four car fires that occurred early April 17. - Photo courtesy of Darren Levitt

Four days later, investigators announced a task force had been formed - with members from the Ann Arbor Police Department, Ann Arbor Fire Department and U-M Department of Public Safety - to probe the suspicious fires.

Brown said investigators do not have any updates in the investigation.

In addition, Ann Arbor police say they're still awaiting results from the crime laboratory in an April 3 house fire on South State Street that claimed the life of a 22-year-old Eastern Michigan University student.

Investigators still don't know whether that fire - which started in a trash can on the porch of the home - was intentionally set. Police say the crime lab analysis may not definitively show what caused the fire.

That blaze occurred the same night three other fires were reported - including one that destroyed three cars.

A reward of up to $5,000 for information about the fires is being offered by the Michigan Arson Prevention Committee.

Anyone with information about the fires is asked to call police at (734) 794-6939 or e-mail Tips@A2gov.org.