Saskatoon fire investigators say a fire that caused an estimated $350,000 in damage to a home in the Riversdale neighbourhood was deliberately set.

The fire at the three-storey residence in the 400 block of Avenue G South was reported shortly after 2 a.m. Tuesday.

Upon arrival at the scene fire crews found the fire had already spread through the front of the home with flames reaching the building's soffits, Saskatoon Fire and Protective Services said in a news release.

Firefighters entered the home to attack the fire but were forced out of the structure due to interior conditions.

The fire posed enough of a threat that residents of surrounding homes were evacuated.

Three firefighters were sent to hospital as a result of battling the blaze, two with heat exhaustion and one suffering light smoke inhalation, but were released shortly after 6 a.m. There were no other injuries.

Meanwhile, a second fire Tuesday morning caused $30,000 in damage to a home on the 400 block of McMaster Crescent.

Crews arrived just before 6:30 a.m. to find light smoke coming from the residence. Firefighters entered the home and were able to confine the fire to the basement furnace room.

No one was home at the time of the fire and officials say there were no injuries.