MORENCI, Mich. -

The Morenci police chief has planned a news conference on Tuesday to discuss efforts to locate three boys missing since Thanksgiving.

In a news release Monday, police say Chief Larry Weeks will provide an update on the investigation and "a shift in the investigative focus."

Nine-year-old Andrew, 7-year-old Alexander and 5-year-old Tanner Skelton were last seen at their father's home in Morenci along the Michigan-Ohio state line.

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Authorities and volunteers searched for the boys in Ohio and Michigan. Weeks has said he doesn't expect a positive outcome.