By CBSLA Staff

LAKE ELSINORE (CBSLA) — Investigators are looking into the cause of a Lake Elsinore house fire that killed two young siblings.

The fire at a Lakeland Village home was first reported at about 2:50 p.m. Monday in the 32900 block of Blackwell Boulevard. Firefighters arrived to find the single-family home fully involved.

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High winds and downed power lines complicated the firefight, but the flames were out by about 4 p.m.

Witnesses said several rooms were on fire, and there was heavy smoke in the garage. A mother, great-grandmother and three children — a two-year-old and a pair of 1-year-old twins — were all inside the home at the time of the fire.

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A 2-year-old boy and one of his sisters died in the fire. The mother and great-grandmother are being treated for critical burn injuries, while the surviving twin girl was taken to an Orange County hospital for treatment.

Several dogs were also hurt.

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The cause of the fire is under investigation.