EL DORADO, Kan. (AP) - The adoptive parents of a Kansas boy missing for about a decade are considered "people of interest" in the case.

Butler County Sheriff Craig Murphy says no charges have been filed in the case, and that investigators are focused on finding Adam Herrman. The boy was 11 when he disappeared in 1999 from a mobile home park in Towanda, where he lived with his adoptive parents, Doug and Valerie Herrman.

No one has reported him missing until recently. His adoptive parents said he ran away.

Murphy said a recent search of the now empty lot where the family's mobile home once stood gave investigators one answer they sought, but he did not elaborate other than to say no human remains were found.

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