(Maryland State Police)

As of 1:45 p.m., the officers were searching Damascus Recreational Park and Little Bennett Regional Park based on information developed during the investigation. Capt. Paul Starks said detectives hope to find William alive, but “we can’t ignore this recent information.”

The search party includes five dog teams and seven mounted horse teams. “A lot of this is heavily wooded” area, Starks said.

The spokesman said detectives also are following leads based on the hope William is alive. The search underway Sunday was an ominous sign, particularly for friends and family members of William’s.

The body of his mother, Jane McQuain, 51, was found Wednesday inside their apartment. She died of stab wounds and blunt force trauma, police said. Police have charged her estranged husband, Curtis M. Lopez, in connection with her murder.

Neighbors and friends said the last contact they had with McQuain and her son was on Saturday, Oct. 1. William has not attended school or sports practices since that day, but police say they have not found evidence that he was harmed.

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Dan Morse covers courts and crime in Montgomery County. He arrived at the paper in 2005, after reporting stops at the Wall Street Journal, Baltimore Sun and Montgomery (Ala.) Advertiser, where he was a Pulitzer Prize finalist. He is the author of The Yoga Store Murder.