NEW YORK (AP) _ A retarded man was punched while strapped in a bed and another was beaten with a leather belt, officials charged following an undercover investigation at a state-run psychiatric center.

Three mental health therapy aides were arrested Wednesday for allegedly abusing patients at Creedmoor Psychiatric Center and five co-workers were charged with selling drugs while on duty.

It was the second bust in two weeks at a state-run facility. On July 14, police made 12 arrests after an undercover agent saw aides slapping, punching and harassing retarded adults at the Bronx Developmental Center.

At Creedmoor, one aide allegedly punched the strapped-down patient in the head because he used abusive language, said Richard Piperno, a spokesman for Queens District Attorney John Santucci.

Another patient was beaten with a belt ''simply because he was making noise and the attendant could not talk on the phone,'' said State Police Investigator Edward E. Delaney.

A third man was forced to kiss and lick an aide's feet - then was kicked and made to eat orange peels and pulp that the attendant already had chewed, said Delaney.

The charges included three misdemeanor counts of endangering the welfare of incompetent pesons, four misdemeanor counts of criminal sale of marijuana and 12 felony counts of criminal sale of a controlled substance, mainly cocaine, Delaney said.

The facility treats 1,300 in-patients and 4,000 out-patients, said Delaney.

The state office set up the undercover agent after some of Creedmoor's 2,500 employees complained to their bosses about alleged criminal activities there, said Steven Osborne, spokesman for the State Office of Metal Health.

The district attorney's office said the patient-abuse suspects face a maximum of one year in jail if convicted. Four drug suspects face a minimum of one to three years in prison; one received a desk appearance ticket.