A male guard at the Montgomery County Detention Center resigned this week after being accused of having sex with a female inmate in one of the center's classrooms.

The county's Department of Corrections and Rehabilitation also is investigating allegations that a second male guard had sex with a different female inmate and that a paramedic at the center gave inmates drugs. The paramedic was placed on administrative leave Wednesday pending the outcome of the probe.

Both the guard who resigned and the inmate who supposedly had sex with him two or three months ago denied the allegation, according to Gary Blake, director of the correction department. Nevertheless, Blake said that when he told the guard Monday about the allegations, the guard offered to resign.

"The last thing I want down there at the detention center is for an officer to utilize his position for something of this kind," Blake said. He declined to name the guard, whose resignation he accepted.

Blake called the evidence against the guard circumstantial. "It was sort of common knowledge among the staff," he said. "He [the guard allegedly] boasted about it."

The incident is believed to have occurred after a class for male and female inmates. When the male inmates left the classroom to return to their part of the jail, the female inmate allegedly remained and was met by the guard, Blake said.

It was the guard's job to patrol an area that includes offices and the classroom where vocational subjects and reading and writing are taught.

The woman inmate was not missed by the guards in her section of the detention center, Blake said, adding, "she was gone only 10 or 15 minutes."

Unlike the male inmates who attend the class, she was not accompanied by a guard because the women's section of the center is next to the classroom, separated from it only by a gate, Blake said.

The inmate was in the center awaiting trial. Officials decline to disclose the charges against her, saying such details might identify her.

Blake said he learned of the alleged incident from a guard who didn't want to be thought of as condoning it. it. "It was all over the jail." Blake said.

Corrections department regulations prohibit guards from becoming involved in personal relationships with inmates or their families. Blake called the alleged sexual contact "stupidity on the guard's part."

The guard who resigned had worked for the department less than a year, he said.

The detention center, as the county jail is called, is on Seven Locks Road in Rockville. It was 300 inmates, 25 of them women. The inmates are either awaiting trial on charges ranging from shoplifting to murder, or serving sentences of 18 months or less.

Blake said police have not been called in to investigate either or the alleged sexual incidents because they apparently occurred with the consent of all parties involved.

Jail administrators investigating the second suspected sexual incident used a police polygraph in questioning a male inmate who allegedly knew what had occurred. Blake said the results of the polygraph test won't be available until next week.

He said the second incident allegedly occurred several weeks ago.

The alleged drug-dealing by the jail paramedic is suspected to have occurred over a period of several months, according to police.