Since the NYPD's closure of Zuccotti Park on Saturday night, a growing number of Occupy Wall Street protesters have set up camp on the south end of Union Square park, some of them sleeping in the park with the NYPD's tacit permission. (According to John Knefel, as many as 100 slept in the park Monday night.) This morning, just after midnight, the NYPD moved in, forcing several hundred people out of onto the sidewalk, and barricading off the southern end of the park. At least one arrest was made—and a protester went into labor during the initial standoff, according to multiple observers.

"I have lived in #NYC for 15 years & I have never seen #UnionSq shut down, not even after 9/11. Who is the terrorist now #Bloomberg? #OWS" — Occupy Wall Street (@OccupyWallStNYC) March 21, 2012

A woman behind the police line just went into labor. Protesters begged 2 let her out 2 deliver. Being lifted into ambulance now. #UnionSq — Occupy Wall Street (@OccupyWallStNYC) March 21, 2012

What's the long-term plan here, NYPD? To close every park in NYC to the entire public forever? That'll go over well. #ows #OccupyUnionSq — Carrie M (@CarrieM213) March 21, 2012

City parks (unlike Privately Owned Public Spaces [POPS] like Zuccotti Park) close at 1 a.m., but this curfew has almost never been implemented in Union Square, at least not that we can remember—not even in the wake of the 9/11 terror attacks, when the park became an impromptu candlelight memorial.

As of 2 a.m., the north side of the park remained open, but protesters remained on the sidewalk outside the park's southern tip, with one man "taunting" police with a donut on a string. According to one protester, the park will reopen at 6 a.m. Just before 3 a.m., another protester tweeted, "Cops moving in, telling us we can't be lying down on the sidewalk. #OccupyUnionSq #pffffft." The NYPD press office does not yet have an arrest count, but, so far at least it seems, there were few arrests.

Update: The NYPD says six people were arrested on a variety of charges, including disorderly conduct, resisting arrest, and obstructing governmental administration. And it appears the woman whom witnesses thought was going into labor was not. On Twitter, one Sadie De Thorn writes: "I DID NOT GO INTO LABOR...AND DO NOT ASSOCIATE ME OR MY UNBORN CHILD WITH THAT RIDICULOUS PROTEST!!!!"

In an email, she elaborates: "I was a bystander that just happen to be at the wrong place at the wrong time. I do not agree with the methods of the real protesters even though I am fully aware of the cause. I do not wish to be associated in anyway with the protesters or their occupation of Union Square, NY. All I am asking is to correct the label of me being a protester and/or occupier. I was a bystander who was waiting for friends with other friends who also was not part of the protest or occupation." Turns out she was having false labor pains and is doing fine now.