County police said yesterday that they are investigating "possible suspicious activity that might be occurring in the intensive care unit" of the Prince George's General Hospital. The investigation was initiated by a request from hospital officials.

Neither hospital nor police officials would explain the details of the investigation. But hospital employes who asked not to be identified said an internal probe, which began 10 days ago, was related to the condition of a patient who suffered heart failure three times for unexplained reasons while in the intensive care unit. The patient survived the attacks.

Carol Bragg, president of the Prince George's Staff Nurse Association, said that one registered nurse who had been assigned to the intensive care unit was placed on administrative leave.

Hospital spokesman Michael Canning said that a preliminary review of hospital records was "inconclusive," but in "the public interest" the data were turned over to police.

Canning also said "administrative action was taken immediately . . . to remove from patient care areas, any individuals suspected of being involved with these unusual incidents." Canning refused to name anyone under investigation.

Maj. James Ross, head of the police Criminal Investigation Division, said hospital officials informed police of the matter Monday night, and so far police have found no evidence of "criminal wrongdoing."

Last night, Bragg said that Jane Bolding, a nurse who has worked at the hospital since 1976, has been questioned by police in the investigation. Bragg said Bolding went to police headquarters yesterday afternoon for the questioning, and at Bolding's request, Bragg asked a labor lawyer to go to the police station yesterday.

The lawyer, Lyn Ermer, said last night she stayed at the police station from 2:40 to 8:30 p.m., but was not allowed to speak with the nurse and was told that Bolding did not want to see her. Police would not say whether they were questioning anyone in the case.

Bragg said, "I have been given no information" by the hospital.