Jared MalsinA demonstrator taunted officers with a doughnut on a string.

At least one person was injured and another arrested when police confronted Occupy Wall Street demonstrators in Union Square early Wednesday morning.

Shortly after midnight, police moved protesters, some of which had been sleeping in the park since Saturday night, off of the south steps of the square and onto the sidewalk before sweeping through the encampment and rousting reclining protesters.

Police arrested activist Yoni Miller, 18, of Brooklyn, dragging him away by the shoulders. In an interview with The Local moments before his arrest, Mr. Miller said, “I think we will eventually be arrested.”

Jared Malsin

“I will stay here as long as necessary,” said Mr. Miller, who works as a freelancer for the website Online Math Circle. “And especially once it starts getting light around 8 a.m., more people will realize what’s going on, where we have a police occupation here.”

Around 4 a.m., during another police sweep through the crowd, a woman, reportedly a volunteer medic, was knocked to the ground during the chaos, and removed on stretcher. In live-streamed video, a member of the crowd alleges the woman was shoved to the ground by a police officer. This could not be verified by The Local.

Some 50 police officers, some wearing helmets and carrying batons arrived on the scene just before 12 a.m., announcing that Union Square Park would become off-limits at midnight. After the park was sealed, a long standoff ensued, with some 150 demonstrators massed at the metal barricades installed by the police.

The face-off took on an air of the absurd when one demonstrator taunted the police by dangling a doughnut on a string over the barricades while the crowd chanted, “No doughnuts, no peace, feed the police.”

In spite of the confrontation with police, some activists were optimistic about the trajectory of their protest. “I think they’ve kind of reestablished our occupation for us,” said protester Lauren Digioia, 27, of Brooklyn, referring to the police. “We can outlast them. We go without sleep, and we’re very, very determined.”

“I think there’s just a die-hard group out here that wants to continue to make a statement,” said Ms. Digioia, a former waitress who now works as a housekeeper in a Brooklyn youth hostel.

Update: The Local’s video of Mr. Miller’s arrest (one of six, according to City Room) is here.