ROCKVILLE, Md. (AP) — Authorities will again be searching for two Maryland children who disappeared last September, but police say they don’t have any new leads.

Montgomery County police and police from other agencies plan to conduct a search Sunday for 3-year-old Sarah Hoggle and 2-year-old Jacob Hoggle. They were last seen Sept. 7. Police have said they believe the children are dead, and authorities are pursuing a homicide case against their mother, Catherine Hoggle, who police have said has been diagnosed with paranoid schizophrenia.

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Police are asking residents who live in the Darnestown, Boyds and Clarksburg areas to again search their property for any sign of the children.

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Police say that because there is an active criminal investigation associated with the children’s disappearance, community volunteers cannot be used in the search.

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