By KATHARINE WEBSTER

Associated Press Writer

BOSTON (AP) -- A teen-ager charged with phoning in fake bomb threats was released from jail Saturday after the telephone company discovered it made a mistake tracing the calls.

Walter Ray Hill Jr., 18, was arrested Thursday and accused of calling police twice to say there were three bombs in the elevators at Boston City Hospital. Nobody was evacuated.

NYNEX traced the calls to the apartment of one of Hill's friends, and witnesses said Hill had been using the telephone there at the time of the threats.

But NYNEX officials making a printout of the call tracing procedure discovered that a company worker had accidentally transposed digits during the tracing process, NYNEX President Donald Reed said.

``An unfortunate human error was made,'' Reed said. ``On behalf of NYNEX, I would like to apologize ... to Mr. Hill and his family.''

The calls were among many bogus bomb threats Wednesday after the bombing of a federal building in Oklahoma City.

Hill's arraignment Friday was delayed for two hours by a bomb scare at Roxbury District Court. Hill, who had no previous arrests, pleaded innocent to falsely reporting the location of explosives.

After being told of the mistake Saturday afternoon, a judge quickly reduced Hill's bail from $20,000 to personal recognizance and police took him home, apologizing to him and his family.

Suffolk County District Attorney Ralph Martin II said he would ask a judge to formally dismiss the charge on Monday.

There was no way to determine who actually made the false bomb threats.

``The effort made to trace the call cannot be recreated,'' he said. ``The case is essentially over, unless we get new information.''

Hill could not be reached for comment. He lives with his parents, who do not have a listed number in the Boston area.

AP-WS-04-22-95 2146EDT

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