The Chatham-Kent fire department said firefighters responded to the first blaze at 475 Wallace St. on Saturday just after 7 p.m. Fire officials said the blaze was contained to a third-floor apartment but several apartments below suffered water damage.
No one was injured and the cause of the blaze remains under investigation.
Fire crews were then called to another fire at 595 Wallace St. shortly after 3 a.m. on Sunday after smoke was seen coming from the boarded-up, multi-unit property.
Firefighters were able to quickly extinguish the fire, however, it took several hours to gain access to the boarded-up building.
The property was empty at the time of the fire and no injuries were reported.
The cause of the fire remains undetermined and a damage estimate is currently unknown.