A man who had just returned from a trip to Great Britain was charged yesterday with stabbing a security guard inside the British Embassy, 3100 Massachusetts Ave. NW, D.C. police reported.

The victim, Terry Hopkins, 31, was listed in stable condition at Georgetown University hospital with a knife wound in his back. Police, aided by the Secret Service, arrested Samuel C. Ostrow, 24, listed at 10630 Kenilworth Ave., Bethesda, and charged him with assault with intent to kill.

Police said Hopkins reported that he was approached inside the embassy door by a man who asked him whether he was a British subject. When Hopkins said he was, the police report continued, the man brandished a knife and chased and stabbed him.

Police said they could not establish a motive, but learned that Ostrow recently had returned from a trip to Great Britain.

In an unrelated incident, Elizabeth Stratton, 86, was stabbed in an eye in a recreation room in the Dix Building at St. Elizabeths Hospital, where she is a patient, police reported. She was in critical condition last night at George Washington University Hospital. A 17-year-old patient at the hospital, accused of the stabbing, was placed in isolation.