The U.S. attorney's office will reopen its grand jury investigation into the 1984 death of Catherine Fuller to consider new evidence that other persons, in addition to the 13 who have been charged, participated in the fatal beating of the 48-year-old Northeast Washington woman.

Assistant U.S. Attorney Jerry S. Goren said yesterday prosecutors had decided to reopen the investigation -- already called the most extensive in the District's history -- as a result of trial testimony that implicated persons other than the 10 now on trial, two who have pleaded guilty and another awaiting trial.

Meanwhile, the jury considering kidnaping, robbery and murder charges against the 10 young defendants deliberated yesterday for the third consecutive day without reaching a verdict.

Goren, who has worked on the case for more than a year, revealed the grand jury plans during a hearing in which Chief Judge H. Carl Moultrie I of the D.C. Superior Court permitted authorities to obtain hair samples from a man originally charged with Fuller's death, but not indicted. Hair that did not match Fuller's was found on her clothing and body.

Goren told Judge Moultrie that charges against 20-year-old Darryl Murchison were dropped after the nine-month period required for grand jury action passed with no indictment, but that new testimony "further implicated" Murchison in the Oct. 1, 1984, slaying.

Calvin L. Alston, who pleaded guilty to second-degree murder and was one of the government's key witnesses in the trial that has lasted more than a month, testified that Murchison was present when a plot to rob someone was hatched, and said "I'm game" when Fuller was pointed out.

Alston testified that Murchison joined in the beating of the 99-pound woman after she was pushed into a Northeast alley, and later said, "Let me see," when Fuller was assaulted with a pole.

Goren said yesterday that new evidence would be presented to a grand jury "very soon." It was unclear yesterday whether the original grand jury, whose term expires in March, or another panel would be used.

The original grand jury interviewed more than 400 people in Fuller's slaying.

Prosecutors have alleged throughout their year-long probe that dozens of people were present in the alley when Fuller was beaten to death. The 13 now on trial or awaiting further court action represent the largest number ever charged in the District with a single slaying.

Several defense lawyers raised the possibility of "Fuller II" in their summations to the jury, noting that prosecution eyewitnesses identified by name a number of other people who they alleged were participants or bystanders in the Northeast alley. In addition to Murchison, the witnesses implicated several youths under the age of 16 who were never charged and at least two persons who were charged, but not indicted, in Fuller's death.

The U.S. attorney's office cannot charge youths under 16 years of age with murder, and a spokesman from the city agency that prosecutes juveniles -- the corporation counsel -- would not say whether that office had begun an investigation into the new allegations made at the trial.

Opposing the government's request to take hair samples, Murchison's lawyer, Josiah Lyman, told Judge Moultrie that the government had been given an "abundance of exculpatory" information that placed Murchison at his job in a fast food restaurant and not in the alley when Fuller was being killed. He cited timecards and testimony from an assistant manager of the restaurant.

Lyman also blasted prosecutors for reopening their investigation against Murchison after holding Murchison in jail for nine months pending grand jury action. A person can be held in jail without bond in the District for nine months before charges must be dismissed if an indictment has not been returned.

"There is nothing new as far as evidence or statements" that is different from what was presented to the grand jury during their its initial investigation, Lyman said. "It is crystal clear the grand jury chose to ignore" the charges.

Goren responded that "no grand jury at any time ever ignored the case against Mr. Murchison."

One source not connected with the U.S. attorney's office said the grand jury did in fact give Goren permission to indict Murchison and three others arrested in the case, but that Goren decided not to approve indictments against the four. At the time, this source said, Alston had provided police with a videotaped statement implicating Murchison. At that point, Alston had not pleaded guilty and consequently his statement could be used only against Alston and references to others would have been eliminated.