Firefighters were called to the Tuscan Cove apartments on Baker Drive near 34th St. E at about 8 p.m. and arrived to find flames coming from the second floor.
The injured residents were taken to the hospital with first and second degree burns.
Six families were affected by the fire, but apartment management said it will move those displaced into vacant units within the complex.
Officials believe it started as an electrical fire involving a Christmas tree.
If you are using Christmas lights this year, keep in mind that you'll want to inspect them to ensure you don't have an electrical short.
You should also turn off all decorations at night, especially when you're not home.
Officials also recommend using flameless candles because no real fire is involved.
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