RENO, Nev. (AP) — Interstate 80 has reopened near the California-Nevada line where firefighters now estimate 20 percent containment of a blaze that's burned through about a square mile of rugged canyons west of Reno.

A 25-mile stretch of I-80 has been closed off-and-on since the fire broke out Monday. Traffic was stopped in both directions Tuesday morning when flames burned within 15 feet of the highway along the Truckee River southwest of Verdi.

The California Highway Patrol says traffic that was backed up for miles is moving in both directions, but with some lane restrictions and intermittent stops for safety checks.

Fire officials say about a half dozen structures were potentially threatened but no evacuations have been ordered.

The Sierra Front Interagency Fire Center estimates 670 acres have burned. No injuries are reported.