Police launched a public safety alert on Sunday evening, after at least three fires were set ablaze in the downtown core.
Two of the fires were sparked inside dumpsters, one at 255 Wellington Street West and another at 50 John Street.
A third fire was also reported at 400 Front Street West inside a care.
Officers say the reports came in a little before and after 6 p.m. and up to two other locations were also targeted.
They believe one suspect caused the fires and have described the alleged arsonist as a white male wearing dark pants, a baseball cap, blue bag and a grey jacket. He was also seen riding a white mountain bike.
PUBLIC SAFETY ALERT:
-Reports of 4 different fires
-May be 1 man setting them
-Male, white, grey jacket, dark pants
— Toronto Police OPS (@TPSOperations) April 23, 2017
Anyone with information is asked to contact police.