A New York senator on Sunday asked Secretary of Defense Donald Rumsfeld to send an elite military unit to search for human remains at ground zero after hundreds of new bone fragments were found at an adjacent building in recent months.

The White House has said that it would let local authorities handle the recovery of remains, but Sen. Charles Schumer, D-N.Y., said that the recent "miraculous" discovery of so many new bone fragments warrants more extensive recovery efforts involving the federal government.

Some family members of Sept. 11 victims said the recent discoveries have given them hope that DNA from the more than 1,000 victims still unaccounted for might be recovered more than four years after the attacks at the World Trade Center.

In a letter to Rumsfeld, Schumer echoed recent calls by Sept. 11 family groups for the U.S. military to deploy its JPAC, or Joint POW/MIA Accounting Command unit, to augment the work of local agencies at ground zero.

JPAC's Hawaii-based forensic laboratory has identified more than 1,200 servicemen dating to World War I. Though the unit is tasked with accounting for Americans missing as a result of the nation's conflicts, it had sent a forensic dentist to ground zero in the aftermath of the attacks, Schumer said. Last year, the unit was brought in to assist in recovery efforts after Hurricane Katrina slammed into the Gulf Coast.

Schumer said a renewed search should include all the buildings bordering ground zero and possibly others nearby, which might have collected particles including bone fragments dispersed by the force of explosions and collapse of the two towers.

Schumer's letter to Rumsfeld follows Friday's announcement that nearly 150 new bone fragments were found in recent weeks on the former Deutsche Bank building's roof. City officials had said they searched the area around ground zero in the months after the attacks.

Nearly 600 bone fragments have been found at the building since workers began preparations last fall to dismantle it. The 41-story building sustained severe damage on Sept. 11, 2001, when the trade center's south tower partially collapsed on it. It has since stood vacant, contaminated with asbestos and trade center dust.

The Skyscraper Safety Campaign, a group founded by Sally Regenhard, whose firefighter son died in the attacks, also recently began a letter-writing campaign to get the federal government involved in the search.