Butler County Sheriff Craig Murphy displays an undated fourth-grade photo of Adam Herrman on Monday in El Dorado, Kan. The Butler County Sheriff's Department is searching for Herrman, who was last seen in 1999.
Investigators only recently learned Adam Herrman was missing and are focused on finding him, Butler County Sheriff Craig Murphy said. Adam was 11 when he disappeared in 1999 from a mobile home park in Towanda where he lived.
Authorities would not say whether they believed Adam, who would now be 21, is alive. "We are working it as if it is a death -- but we are not leaning one way or the other," Murphy said.
Doug and Valerie Herrman adopted Adam at 2 1/2 years old, and he had been in foster care before that. The parents have not been arrested or charged with any crime, and Murphy said no charges would be filed while investigators focused on the search.
The family's attorney, Warner Eisenbise, said his clients did not harm the child. He said the Herrmans are innocent of any wrongdoing other than not reporting their son missing, which is against Kansas law.
"He was a problem child. He ran away frequently to the point of exasperation," Eisenbise said. "My clients feel very guilty that the last time he left they didn't make an attempt to locate him. Every other time, the police were called or he wandered back. They assumed he found one of his siblings or went back to his biological parents."
Murphy said investigators have not confirmed whether Adam had a history of running away. The family has cooperated with investigators, he said.
The Herrmans now live in the Wichita suburb of Derby, in neighboring Sedgwick County.
Adam was homeschooled when he disappeared, Eisenbise said.
Murphy said a search of the 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.
Murphy's office did not receive a missing persons report until contacted recently by Sedgwick County's exploited and missing children's unit. He declined to say who tipped them off. It was not clear exactly when they learned of the boy's disappearance.
Investigators have not found any confirmed data on Adam's whereabouts since 1999.
Murphy asked the public for help and issued a plea to the missing boy himself: "If Adam Herrman is alive out there -- and he would see this -- I would ask him to contact us immediately."