A 23-year-old woman was found dead in a Rockville motel room yesterday after testifying as a prosecution witness in a trial stemming from the murder of her sister. Police called the death suspicious.

The woman, Vivian Levy of Providence, R.I., had testified Monday in a perjury trial that grew out of the Jan. 2, strangling of her sister Claire, 24.

Vivian Levy's body, fully clothed and showing no external sign of injury, was found face down between two beds on the floor of her room in the Rockville Ramada Inn.

The woman checked into the motel Sunday night. Police found the body about 2 p.m. yesterday after the woman's relatives became concerned and telephoned the motel's management.

The events that brought Levy to Rockville this week began Jan. 28 when she returned at 5 a.m. from a job as a waitress to the apartment she was then sharing with her sister at 8039 Eastern Ave. in Silver Spring.

Vivian Levy found her sister body in her bed. Hours later, police said they arrested a 23-year-old Washington man described as a "friend of the family" and charged him with murder in Claire Levy's death.

The man was identified as David Leander Stratmon Jr. of 7573 Alaska Ave. NW.

Charges against Stratmon were dropped, however, after a preliminary hearing at which a woman identified as Stephanie Walker testified, according to a spokeswoman for the Montgomery County prosecutor's office.

Walker was later charged with perjury in connection with her testimony at the hearing, the spokeswoman said. Vivian Levy testified in Circuit Court Monday as a prosecution witness at Walker's trial, authorities said. The trial is continuing.

Police who found Vivian Levy's body said they found no signs of struggle or forced entry into her motel room. A police spokeswoman said an autopsy will be conducted today to determine the cause of death.