Thirty-eight-year-old Michelle Smith was being held at the El Paso County jail on Wednesday on suspicion of arson. She was arrested Tuesday after the fires were extinguished in Sijan (Sigh-jahn) Hall.
Academy spokesman Meade Warthen said cadets were safely evacuated and there was no structural damage. About 2,000 cadets live there.
Two small fires also broke out in the dorm Friday. Warthen said investigators don't know yet whether the two sets of fires are related.
It wasn't known whether Smith has a lawyer.
The Gazette reports that according to an arrest affidavit, Smith allegedly told an investigator the fires were set because she was upset, lonely and depressed.
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