Updated

Through unstinting smoke and endless tears, weary cleanup workers paused for a moment at ground zero Thursday to mark a grim milestone — the passage of one month since New York's Twin Towers ceased to exist, along with thousands of people trapped inside.

"Don't look at the terrorism over there, look at the heroism over here," said Rabbi Joseph Potasnik, a Fire Department chaplain, as workers took off their helmets and joined arm in arm.

Fire Department bagpipers played "Amazing Grace," their pipes decorated with small American flags. They led police officers, firefighters and construction workers to the service, which included a moment of silence at 8:48 a.m., the time of the first attack on Sept. 11.

The ceremony at the World Trade Center was just the first of several planned both in New York and outside of the city. President Bush was scheduled to speak at a memorial service at the Pentagon, where 189 perished the same morning.

At the New York Stock Exchange, representatives of New York's uniformed services rang the opening bell, and received a lengthy ovation.

At the trade center, as bright sunlight pierced the smoke that has persisted for a month, prayers were offered first for the 343 firefighters and 23 police officers who were killed, and then for all the dead. So far, there are 422 confirmed dead and 4,815 listed as missing. In addition, 157 people on the planes were killed.

"The fire is still burning but from it has emerged a stronger spirit," Mayor Rudolph Giuliani said, as he stood with the city's fire and police commissioners on a stage in front of the blackened Dow Jones building.

"Sometimes it feels like yesterday, sometimes it feels like a year ago or more," he said. The terrorists, he said, "attempted to break our spirit — instead they have emboldened it."

It was a brief service, just 15 minutes long; the idling engines of the heavy construction machinery could be heard in the background. The 23rd Psalm was read, and prayers were offered. At the end, the pipes played "America the Beautiful."