Later Sunday, the Rev. Jesse Jackson, a vocal supporter of the Occupy Wall Street protests, visited the Philadelphia encampment.
At the news conference, Nutter voiced frustration at the difficulty of communicating with protesters who he said had repeatedly failed to follow through on promises made during seemingly cordial meetings. He said a key problem was continual change in those who tried to speak for the protesters.
"Many of the people that we talked to from the beginning of this event and activity are now gone," Nutter said. "And Occupy Philly has refused to engage in active, regular discussions with us."
Nutter said city officials were especially worried about the presence of tents, bedding, and other flammable materials on a densely packed site where campers have been using lanterns, candles, and even propane heaters. At least one tent has been destroyed by fire, he said.
"It is now abundantly clear that on many levels, this group is violating a range of city ordinances and the terms of their permit," Nutter said. "Of necessity, we are now at a critical point where we must reevaluate our entire relationship with this very changed group."
Some Occupy Philly participants questioned Nutter's timing and motives, along with some of his assertions. At the same time, some acknowledged that minor crime has been a problem and perhaps inevitable as protesters live alongside some of the city's homeless population and other transients.
"I think he's being unfair in a lot of the language that he's used," said Jesse Kudler, 31, a West Philadelphia resident who works for a nonprofit arts organization.
"This is one of the first statements the Mayor's Office has put out since the election," Kudler said. "There's a lot of speculation that the tone from his office has changed because this is no longer a potential campaign issue."
Kudler said Nutter "essentially painted us as intransigent, intractable, unsafe, and radical, when it's not clear how the facts on the ground have changed."
Alan Sable, a former union organizer, said Nutter was wrong to suggest that the group's leadership had changed significantly. And he disputed Nutter's suggestion that the protests had grown more radical.
"From the beginning, the Occupy Wall Street movement had been about nonviolent protest and civil disobedience," Sable said, adding that Nutter "may feel uncomfortable because of the increasing protests against his curfew policy and the targeting of some of his corporate cronies, like Comcast," whose Center City headquarters were the target of two recent protest marches.
Nutter said that the city did "not seek confrontation with Occupy Philly" and that he shared many of the concerns voiced by protesters here and around the country about poverty, joblessness, and banks' lending practices.
But he alluded repeatedly to one of the Occupy Wall Street protesters' most familiar slogans - "We are the 99 percent" - as he said the city must do what is needed to clear the area for scheduled City Hall repairs and the multimillion-dollar redesign of Dilworth Plaza.
"As mayor of the City of Philadelphia, I represent the 99 percent also," said Nutter, who suggested the protesters should support a project designed to turn the plaza into "an open, green, vibrant space built by the 99 percent for the 99 percent."
"The Dilworth Plaza project will not be conducted by some corporate entity," he said. "These are real men and women - Philadelphians, Pennsylvanians - who need jobs, who need to take care of their families, their 99 percent, in their households. That's what this is about."
The decision to stay at Dilworth Plaza has been challenged by at least some protesters via an online petition that had 91 signatures Sunday night.
Signers said they felt that "by adopting a strategy that will inevitably lead to a conflict, issuing a statement that we will resist eviction, and inviting confrontation, the decision is in direct violation of the 99% movement's core principles of peace, nonviolence, and inclusiveness."
Contact staff writer Jeff Gelles
at 215-854-2776 or email@example.com.