ROCKVILLE, Md. (AP) — The father of two suburban Maryland children missing for more than three weeks is appealing to Gov. Martin O’Malley for help.

Troy Turner of Clarksburg sent a letter to O’Malley on Monday morning saying he’s seen no evidence ruling out that his children may be alive and believes an Amber Alert would help find them. He asks the governor to intercede with Maryland State Police and have the agency issue an Amber Alert for 3-year-old Sarah Hoggle and 2-year-old Jacob Hoggle.

Montgomery County police have said they believe the children are dead and were pursuing a homicide case against their mother, 27-year-old Catherine Hoggle. Hoggle is being held on charges related to her children’s disappearance. Police say she has been diagnosed with paranoid schizophrenia.

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