New York's bravest turned against New York's finest Friday during a protest of a plan to cut down on search-and-rescue teams at Ground Zero.

Some of the hundreds of firefighters demonstrating were arrested for scuffling with police near the site of the World Trade Center disaster in Lower Manhattan. Mayor Rudolph Giuliani had announced the staffing cutbacks in the Ground Zero rescue searchers earlier this week, citing worker safety.

"Mayor Giuliani, let us bring our brothers home," read one sign at the rally near the site, where 343 firefighters and 23 New York City police officers were among the thousands of people lost Sept. 11.

Police said there were 12 firefighters arrested for fighting with police. Five police officers were injured.

Those in custody were charged with inciting to riot, assault, trespass, disorderly conduct, and obstructing governmental administration. Among those arrested are three top union officials, said Peter Gorman, president of the Uniformed Fire Officers Association.

When police initially refused to let demonstrators into the sealed-off area around the collapsed towers, some of the firefighters tangled with the boys in blue. After a few minutes, the firefighters continued on their march, then paused for a minute of silence.

The group marched a few blocks to personally deliver their message at City Hall, where police in riot gear and officers on horseback stood by.

"Our message has been delivered. If we come back here again, we'll come back with 5,000," Gorman said as the protesters stood outside a gate at City Hall.

Once there, the marchers observed a second moment of silence before singing "God Bless America." There were no clashes with police at that scene.

Firefighter Bob McGuire, whose nephew Richard Allen was among those missing in the rubble, said remains had been loaded into trash bins.

"I don't want him to end up in a Dumpster," McGuire said.

"Do the right thing!" the protesters chanted as they listened to union leaders give speeches on bullhorns next to a chain link fence decorated with an American flag.

The firefighters, joined by members of other unions, have worked virtually nonstop at the scene since the towers collapsed.

Giuliani said he wants no more than 24 firefighters and 24 police officers at Ground Zero at any one time.

The firefighters' union says it fears that would turn the recovery effort into a "full-time construction scoop-and-dump operation."

"The reduction in emergency personnel is really an attempt to speed up debris removal, and it is upsetting to the families," Gorman said.

The firefighters' sole concern is the remains of their friends and people's loved ones, said Michael Carter, vice president of the Uniformed Firefighters Association.

"That site, besides containing roughly 250 firefighter bodies, also contains many, many, many civilian bodies as well," said

McGuire denied speculation that firefighters wanted to stay at the site to pad their checks.

"This has nothing to do with overtime," he said.

On Thursday, the New York Fire Department added 240 new members to its ranks, handing out diplomas to trainees at a ceremony marked by six empty chairs — seats symbolically held for classmates who died in the trade center collapse.

Thursday's training academy graduates were the first since the terrorist attacks, but they still leave the department more than 100 shy of filling all the places of those lost.

The six trainees who died were awarded diplomas posthumously.

"We will remember their bravery in all that we do throughout our lives," department chaplain Rabbi Joseph Potasnik said.

The New York Times reported Friday that the NYPD faces the prospect of accelerated retirements of veteran officers who can qualify for larger pensions this year because their earnings have been fattened by unprecedented overtime pay since the attack.

Joseph Maccone, who managed the department's pension unit last year and now works for the police officers' union, told the paper:

"Anyone contemplating retirement before, this overtime will definitely make them decide on retiring."

The Associated Press contributed to this report.