Two wildfires burning in southern Arizona

Arizona firefighters were battling two separate wildfires Monday in a mountainous area outside of Tucson. Authorities in the town of Oro Valley said crews made slight progress on a fire in the nearby Pusch Ridge area. The blaze had grown to more than 3.6 square miles (9 square kilometers), according to Oro Valley police's Twitter page. The fire ignited Friday because of lightning and was burning in mostly rugged terrain and not threatening any structures. More than 100 firefighters were working to build containment lines. Authorities said three helicopters were helping to make water drops.

A second lightning-caused fire was burning north of Oro Valley in the Tortolita Mountains. It was more than 5.4 square miles (14 square kilometers) as of Monday but no structures were under threat. Fire officials say it grew thanks to gusty winds a day earlier. It is located in extremely rugged terrain of dry grass and brush, making it challenging for the 90 personnel. Another challenge was that natural water sources were scarce, so firefighters were getting water from the closest town. "We're fortunate that Oro Valley's right by us. There's a shopping center near us. So they're getting the water from the hydrants," said the fire authority's water group supervisor Mathew Mayhall. Oro Valley is roughly 15 miles (24 kilometers) north of Tucson.