Toronto police are stepping up their search for an arsonist that has targeted the Riverdale neighbourhood all summer.

About ten police officers canvassed the area Saturday morning hoping to gather more information five incidents that have been worrying residents since May 2007.

Fires have been set to garages with parked cars inside and in one case, the fire spread to a neighbouring home. The most recent suspicious incident happened Oct. 3 on Pape Avenue.

Detective Constable Stuart Fleming told reporters all incidents happened within walking distance from each other and that the arsonist is probably a local. However, they don't have any suspects.

Officers knocked on a lot of doors, asking residents if they've noticed any suspicious activity in the area. They also gave them tips on what to look out for.

"If there's somebody in the rear laneway, why are they there? Who are they? Do they belong there? If they don't belong there, contact police," Fleming said.

Toronto Fire Services have been busy investigating an unusually high number of suspicious fires throughout the entire city this past summer. Parkdale, a neighbourhood in the city's west-end, was also hit a number of times by arson.

So far, authorities don't have evidence the fires set on opposite sides of the city are linked, an officer at 55 Division told CTV.ca.

"Arson is likely the most difficult crime to investigate purely because the accelerant used can be lit and then the perpetrator can leave the area and just let it burn," Fleming told CTV News.

During the past few months, Toronto has been hit with more than 40 suspicious fires.

Police say the best way to protect your home is to make sure there is adequate lighting around it and to clean up debris, such as newspapers, paint or leaves which arsonists typically use to spark a flame.

Anybody with information is asked to contact authorities either anonymously at (416)222-TIPS or directly to police at (416)808-5504.

With a report from CTV's Galit Solomon