OTTAWA -- Police say a 78-year-old man has been arrested after an arson investigation in Ottawa's south end.

They say a man was seen leaving the area of a fire at a home Sunday morning.

Investigators say there were no injuries in that fire, but police say the home suffered substantial damages.

Police say later Sunday a second home was allegedly lit on fire. Again, nobody was injured, but the home was damaged.

They say that the 78-year-old suspect was identified, and later arrested.

There's no word on charges, and the man hasn't been named by police.

The arson unit is continuing its investigation.