A former guard at the D.C. jail, who was convicted in June of assaulting a visitor there with a blackjack, has been charged with the rape of an 11-year-old Southeast Washington girl.

Isaac Mack Webb Jr, 30, of 2915 Pennsylvania Ave. SE, who is a former D.C. police officer, was arrested Wednesday afternoon after the victim's mother came home from work and discovered Webb and her daughter in an upstairs bedroom.

Last month, Webb was sentenced to serve two-to-six years in prison after a D.C. Superior Court jury found him guilty of assault with a dangerous weapon. Chief Judge Harold H. Greene suspended imposition of the prison term and placed Webb on two years probation.

Yesterday, Judge DeWitt S. Hyde ordered Webb held without bond until Tuesday, when a probation revocation hearing is scheduled before Chief Judge Greene.

A corrections officer for seven years, Webb was informed following his conviction on the assault charge in June that his employment would be terminated, according to a spokesman for the D.C. Department of Corrections.

For the past several weeks, Webb has worked as a janitor at the department's training academy, located at Lorton, Va., pending final action on his dismissal, the spokesman said.

For a year prior to joining the corrections department, Webb worked as a D.C. police officer but resigned for personal reasons, the spokesman said.