Police sealed manholes, removed mailboxes and outlined plans Monday to post snipers on roofs during the big New Year's Eve celebration in Times Square.

City officials have not received any specific threats against the New Year's Eve celebration, but thought it was "better to be safe than sorry," Mayor Michael Bloomberg said. Last year, an estimated half-million people crowded into Times Square.

Photographs of several foreign-born men sought by the FBI for questioning about possible terrorist connections were distributed to officers citywide, Police Commissioner Ray Kelly said. They are believed to have entered the United States from Canada.

At a separate news conference, Gov. George Pataki said he had spoken with Homeland Security director Tom Ridge several times in recent days and "there are no specific threats to New York that I have been advised of."

For the celebration, Kelly said a couple thousand officers will be on duty, similar to last year. Police plan to deploy undercover officers throughout the crowd and put snipers on roofs.

Bomb squads will sweep Times Square, and participants will be searched as they enter the area. Large bags will be prohibited.

Pilots will be banned from flying lower than 2,000 feet over the area.

The mayor will be joined by actor Christopher Reeve and his wife, Dana, in leading the countdown for the dropping of a 6-foot crystal ball at midnight.

The fireworks display that was canceled last year after the terrorist attacks will resume for this year's million-dollar celebration.

Forecasters predicted rain to begin just as the party gets under way, with temperatures in the low 40s.