Andrew Vincent, Steve Fritzoni, David Rackley and Russel Barrett informed Major League Baseball officials of their decision to return home, league administrator Marcos Rodriguez said Monday.

The threat occurred Friday when a fan spotted one of the umpires outside his Santo Domingo hotel, Rodriguez said.

``He appeared to recognize him, turned around, insulted him and threatened to kill him with a pistol,'' Rodriguez said.

It was unclear what might have prompted the threat.

The six-team Dominican League, a winter-ball home to dozens of major league players, was working to replace the umpires, Rodriguez said. No games had been cancelled.