An inmate at the Maryland Correctional Institution in Hagerstown has been charged with rape and armed robbery after police used a DNA sample to tie him to a home invasion robbery two years ago, Baltimore County police said yesterday.

Police said Steven P. Diffendal, 30, is being charged in a warrant with first-degree rape, armed robbery, two counts of first-degree sex offense, three counts of first-degree assault and three counts of false imprisonment in connection with a home invasion and robbery in Parkville on Nov. 26, 2000. Police allege that Diffendal raped a young woman who happened to be at the house.

The case marks the first time county police have located a suspect using the DNA database known as CODIS - the Combined DNA Index System. The database contains genetic profiles of convicted felons and is maintained by the Maryland State Police.

DNA samples are entered into the database and are compared with samples recovered from crime scenes throughout the state.

The samples also are sent to a federal database that compares samples from across the country.

Diffendal, who had no fixed address, was sentenced to 11 years in prison in May 1991 after being convicted on armed robbery, burglary and weapons charges.

He was paroled but returned to prison in January for violating the terms of his parole, police said.

When a new state law took effect last month requiring all defendants to submit DNA samples when convicted of a felony, Diffendal was ordered to comply. The law was made retroactive to the start of the year.

Police said Diffendal's DNA matched a sample taken from the site of the Parkville incident.

Before the law change, only those convicted of sex offenses were required to submit DNA samples.