Last night, Mayor Bloomberg delivered a message to Occupy Wall Street protesters who've been camped out at  Zuccotti Park the past several weeks: the park needs to be cleaned. And protesters, their signs, sleeping bags, and, presumably, portable libraries need to temporarily vacate the premises while the park's property owner can go in with a cleaning crew. Citing this statement from the Deputy Mayor's office, Capital New York relayed that cleaning would begin this Friday in stages. 

The announcement was made after the mayor visited the encampment for the first time on Wednesday evening (NBC New York reports, "Witnesses said his demeanor was cheerful, though he didn't stop to speak to many protesters."). The New York Times, after speaking with a protester who voiced a sensible concern that the park cleaning was just a way to end the protests, noted vague-seeming language from the mayor's office:

The Bloomberg administration added that the park would be cleaned in stages, and that the protesters would be allowed to return to the areas that had been cleaned, “provided they abide by the rules that Brookfield [the park's owner] has established for the park.” It was not immediately clear how long the cleanup would take.

Bloomberg had previously hinted that protestors were free to stay at the park, though he didn't appear pleased that the protesters were marching past the homes of several prominent media moguls, including the residence of JP Morgan CEO Jamie Dimon. And when asked last week how long the protests would last he responded:  "I think part of it has probably to do with the weather."