A Silver Spring couple was arrested early yesterday and charged with assaulting the wife's 69-year-old grandmother, who Montgomery County police said suffered broken ribs and blackened eyes as the result of a beating about two weeks ago.

Debra Lee Paul, 25, and Gregory John Paul, 30, were arrested after the couple barricaded themselves in the elderly woman's home at 709 University Blvd., Silver Spring, for about two hours as the police emergency response team waited outside, a police spokesman said. The couple's 2-year-old daughter was placed in protective custody, according to police.

The Pauls were charged with assault with intent to maim Mrs. Paul's grandmother, Nadia Carlson, who is in Holy Cross Hospital. In addition, Debra Paul, who police said was living in her grandmother's house, was charged with four counts of check forgery and was jailed in lieu of $140,000 bond. Gregory Paul, who lives at 12403 New Hampshire Ave., was held under $100,000 bond.

Carlson's injuries were discovered after someone fired a shotgun blast through a window of her home and police were called to investigate, according to police spokesman Sgt. Harry Geehreng. Carlson, who also has a heart condition, was taken to the hospital at that time, Geehreng said.

The Pauls barricaded themselves in the house late Thursday when police went there to serve the arrest warrants, Geehreng said, but surrendered without incident about 1 a.m.