Tucson fire crews battled a huge fire at Tucson Greyhound Park early in the morning on May 4. TFD says units responded about 3:00 a.m. to the 2600 block of south 3rd Avenue for a commercial building fire. The building was identified as the former Tucson Greyhound Park in South Tucson. Tucson Fire says heavy fire conditions forced crews to take a defensive approach, as well as call in additional resources. TFD says 30 firefighters were used along with one engine company from South Tucson to control the fire, which took 90 minutes. There were no injuries to firefighters and no displaced occupants. The fire cause is under investigation.