No one was hurt in a Southwest Portland duplex fire that extended to two nearby homes, firefighters said early Monday.

The two-alarm blaze appears to have destroyed the duplex, which is on Sherman Street between Sixth Avenue and Broadway Drive. Two adjacent homes were spared destruction because of firefighters’ efforts, according to Portland Fire & Rescue.

SW 6th&Sherman: 2nd alarm duplex fire extended to two homes, witnesses called in when they noticed heavy fire in a duplex near completion of remodel, firefighters focused efforts on preventing spread to very close neighboring homes, no injuries reported #alert @PBOTinfo pic.twitter.com/MvHQH8RZQJ — Portland Fire&Rescue (@PDXFire) February 3, 2020

Fire investigators are still working to determine the cause of the blaze, fire officials said Monday morning.

The duplex was being remodeled prior to the fire. It was unoccupied.

Portland Fire & Rescue asks anyone who has photos, videos or information regarding the initial stages of the blaze to call 503-823-4636.

-- Jim Ryan; jryan@oregonian.com; 503-221-8005; @Jimryan015

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