The fire investigation revealed the blaze originated in combustible chairs on the fifth floor where two hallways intersect.

Toronto police and fire officials have determined the fire at an east-end Toronto Community Housing Corporation (TCHC) building that killed four seniors was intentional.

Sources say the Toronto Community Housing Corporation has been charged under the Ontario Fire Code in connection with a fatal fire at a seniors' building that killed three people and left 12 others hospitalized earlier this month.