Officials believe searching roads near the World Trade Center site could turn up more human remains.

But they will not advise an expanded search at ground zero itself because they do not expect to find remains on those 16 acres (6.5 hectares), according to an official familiar with the plan, who was not authorized to speak about the proposal before it was delivered to the city Friday.

Mayor Michael Bloomberg said Friday that the site "was extensively and completely searched" for remains after the Sept. 11, 2001, terrorist attacks.

While a search continues in manholes along a service road at the site's western edge, "there's no chance for anything else" in parts of the site where construction is under way, Bloomberg said in his weekly radio show.

Deputy Mayor Edward Skyler ordered city and state officials last week to compare search grids and maps of the site with the post-Sept. 11 cleanup and recovery and come up with possibilities for a renewed search.

Skyler, who is overseeing the renewed effort to recover remains, declined to comment ahead of the presentation.

Utility workers came across body parts while digging up a manhole last week under the street-level service road. Since then, workers have uncovered more than 200 bones — ranging from 1-inch (2.5-centimeter) shards to full arm and leg bones. Officials acknowledge that the manhole and several other underground cavities were missed during the initial nine-month search for the dead.

The current search has targeted 12 manholes and service boxes along the service road. Nine more human remains from that area were recovered Thursday, said Grace Burgess, a spokeswoman for the city medical examiner's office.

The proposal does not address the possibility of inspecting the many buildings that surround the site, beyond a search already under way in a 40-story damaged skyscraper just south of the site and an old dormitory that has not yet been searched, the official told the AP.

Fire officials have said the department thoroughly searched buildings surrounding the site for remains.

Bloomberg said Friday that the Fire Department, which lost 343 firefighters in the attacks, "looked and they did the best job they could. Can you keep looking forever? I suppose there's no limit."

Bruce De Cell, whose family received remains of his son-in-law on five different occasions since the attacks, said that the rooftops of area buildings should be searched again, and added that the entire search should not be handled by the city.

"I think it should be put into the federal government's hands," De Cell said. City officials "really have done a haphazard job altogether."