Keith Anthony Longtin, 44, was ordered held without bond last night on a charge of murdering his estranged wife, Donna A. Zinetti, whose body was found Monday morning in woods near her home in Laurel.

According to a statement of probable cause that is part of the charging documents, Longtin exhibited knowledge about the crime "that had not been released to the media and that only the perpetrator would have known."

Longtin, who lives in Crofton, was brought in for questioning Tuesday afternoon, shortly after he appeared at the site where his wife's body was found in the 13100 block of Larchdale Road.

He had been questioned at county police headquarters in Palmer Park for more than 36 hours when he was charged by homicide detectives with first-degree murder about 10 p.m. Wednesday.

Longtin's appearance before a magistrate to have bond set was delayed until about 7 last night, and he was then transferred to the county jail. Police attributed the delay in the hearing to a heavy backlog of cases before the commissioner.

Until Longtin was charged, police insisted that he was not a suspect in his wife's death and that he had voluntarily agreed to answer questions. They said that he was not in custody and that he could leave whenever he wished.

On Tuesday, police said--incorrectly--that Longtin had left the police station that night after being interviewed for several hours and reemphasized that he was not a suspect. Yesterday, police acknowledged that Longtin never left the station.

Cpl. Joe Merkel, a police spokesman, said the error was the result of "misinformation" given to the department's public information office by homicide detectives.

"Initially, he was not under arrest and he was here under his own free will," Merkel said. "At some point during the night, he did go from being somebody who was providing information about a homicide victim to a suspect who was charged."

Zinetti, 36, was last seen about 6:30 a.m. Monday by several neighbors as she went out for a run. Police said she was wearing her jogging clothes when her body was found, stabbed repeatedly, at the crest of a ravine in the Larchdale Woods apartment complex by a neighbor who was walking her dog.

Longtin was taken to police headquarters for questioning shortly after he arrived at the crime scene Tuesday in a battered late-model Buick and began talking to reporters about his missing wife. His eyes moist with tears, he said he had been separated from Zinetti and had last seen her at church on Sunday, when they had "a disagreement."