10:37 p.m. – Police declared the gathering near Schenley an “unlawful assembly” and told protesters to move or risk being forcefully removed.

Previous updates:

10:30 p.m. – Two S.W.A.T. trucks and seven or eight police SUVs just pulled into Schenley. The people stopped dancing, as they had been doing for at least a half hour.

9:55 p.m. – Police have formed a second line. The officers, protected by black riot shields, are telling protesters to disperse.

Protesters are shouting at the officers to tell them the name of the person they took away.

Fifteen police vehicles drove down Bigelow Boulevard. They’ve stopped in front of Hillman Library and turned off their lights.

The Hare Krishnas are still playing music.

9:45 p.m. – Police took a protester behind the police line. It’s unclear if they’ve made an arrest.

There are less than 200 people left at the protest, and police backed the demonstrators onto the curb of Shenley Plaza.

Hare Krishnas played music for the crowd, and people danced to the beats of drums and cymbals.

Police are still calling in additional forces to help disperse the crowd near Schenley Plaza.

A group of S.W.A.T. officers now extends from the Carnegie Library, across the traffic light to the fountain in front of the Frick Fine Arts Building.

City Councilman Bill Peduto is near the gathering, talking to reporters.

He said he’s been visiting protests throughout the day telling demonstrators, “Don’t do something that would put anyone in danger.”

Peduto guessed that the crowd around Schenley includes closer to 1,000 people.

Some police officers are videotaping the crowd.

7:06 p.m. – The rioting near Schenley Park is beginning to escalate again.

After police sent additional officers in on a Port Authority bus, what looked like at least 100 people ran away from the crowd of 400 to 500 people.

Police then began jumping out of their lines, scaring dozens more people away.

Some of the demonstrators began returning when they realized the police, at least for the moment, were not using physical force.

6:54 p.m. – An anti-protest movement has begun near Schenley Park and the Phipps Conservatory, causing police to send in an extra busload of officers.

The original protesters were screaming “This is not what Democracy looks like” and “Your ideas are impractical” a few moments ago.

Some people cheered.

Another group began mocking the protesters by screaming “U.S.A. U.S.A. Apple Pie. F*ck yeah. Hot dogs. F*ck Yeah.”

6:38 p.m. – Police, protesters and observers are facing off near the near the entrance to Schenley Park.

About 50 people gathered on Schenley Drive around 4 p.m. in hopes of watching President Barack Obama drive to Phipps Conservatory, in the park.

Obama, his wife and the other G-20 leaders and spouses are holding a working dinner in Phipps, one of the first official events of the G-20 Summit.

Additional police arrived to monitor the crowd, which multiplied as time passed, and placed caution tape on the Schenley Drive side of the intersection.

A few people ripped down the caution tape and began leap-frogging over each other, toward the police.

The police using a megaphone declared the event and “unlawful assembly.” When the crowd didn’t move, the police used a smoke bomb to try to get them to disperse.

People are still gathered near the entrance to the park chanting and playing musical instruments.

6:16 p.m. – Mounted police rode down Schenley Drive a few moments ago, sending people gathered near the entrance of Schenley Park back toward campus.

About 15 minutes before, the police had used a smoke bomb to try to disperse the crowd, which was less than a half mile from Phipps Conservatory.

The G-20 leaders and their spouses are holding a working dinner in Phipps Conservatory in one of the first official events of the Summit.

Police had asked the people to disperse, calling their gathering an “illegal assembly.”

A small group of people stood in front of the police chanting, “Whose streets are these?” “The Steelers just won.”

Another, larger group of people stood behind the protesters observing.

5:52 p.m. – Police released a smoke bomb on people gathered near the entrance to Schenley Park, many of whom were Pitt students.

The G-20 leaders and their spouses are currently in Phipps Conservatory, in the park, for a working dinner. The dinner is one of the first official events of the Summit, which runs through tomorrow.