Rush hour traffic on Tucson’s south side was diverted Tuesday morning while firefighters battled a blaze at a vacant house.

Multiple calls from passersby reported the fire just after 8 a.m. in the 1700 block of South Park Avenue at East 26th Street, said Capt. Barrett Baker, spokesman for the Tucson Fire Department. They saw flames coming from a water heater attached to the exterior of the home.

It took crews just three minutes to bring the blaze under control. The cause of the fire is under investigation, he said.