The execution Tuesday night of Morris Odell Mason, a 32-year-old murderer who once called himself "the killer for the Eastern Shore," ends the likelihood of any more executions in Virginia until late this year, a state spokesman said today.

Mason's death in Virginia's electric chair at 11:07 p.m. brought to three the number of executions in the last eight months and leaves 28 men on the state's death row, said David Hathcock, spokesman for state Attorney General Gerald L. Baliles.

Of the 28, only three have execution dates, but Hathcock said "none is realistic because they are so new in the appeals process."

Michael M. Smith, who has been on the state's death row longer than any other inmate, was denied a new trial today by the 4th U.S. Circuit Court of Appeals.

Hathcock said it is possible that Smith could be given an execution date by year's end if an expected appeal to the Supreme Court also is denied.

Smith, convicted of the May 1977 rape-slaying of a woman along the Colonial Parkway near Williamsburg, was the first person sentenced to death in the state after the Supreme Court's 1976 ruling allowed executions under certain conditions. Prior to that time, the state had not executed anyone since 1962.

Hathcock said next spring is a more realistic date for any further executions after Smith.

Mason, who pleaded guilty to rape, murder and arson in the 1978 slaying of 71-year-old Margaret K. Hand, died hours after Gov. Charles S. Robb rejected final pleas to spare his life.

Prison officials said he had no final statement, although he earlier apologized for his crimes.

"I'd like to tell all of 'em that I'm sorry and everything and to forgive me and everything," Mason said. "If I hadn't been on drugs, it wouldn't have happened."

Mason, whose attorneys contended he was mentally retarded and did not comprehend his crimes, talked quietly with family members by telephone and ate two Big Macs brought in from a McDonald's restaurant in the hours before his execution.