When push came to shove in Yorkside Pizza and Restaurant early Sunday morning, witnesses said, many patrons soon found themselves in the midst of a short-lived brawl that filtered into the street as police arrived.

At around 2:00 a.m., two diners sitting in the middle of Yorkside started a shoving match, witnesses said, which quickly grew as their friends became involved and those nearby were pushed around. At the fight’s peak it stretched from the ordering counter to the door, but the police arrived within minutes and defused the situation. Some present said the police utilized a type of tear gas or some other chemical substance, though the New Haven Police Department could not confirm whether any such measure was used.

John Mittermeier ’08 said he was standing in the middle of the restaurant when tensions began to develop between two patrons nearby.

“Some Yale guy was talking to his friends by one of the middle tables, [and] he bumped into another guy and they picked a fight from there,” he said. “A couple of the other guys’ friends [joined], and it kind of snowballed from there.”

The New Haven Police Department declined to comment on Sunday.

Mittermeier said the fighting — in which about 20 people were soon involved — mainly involved shoving, though some punches were thrown as well. Sections of the restaurant resembled a “mosh pit” as the fight spread towards the door, he said. Some people were caught in the struggle, he said, though most were able to get out of the way.

He said the Yorkside employees mainly stayed out of the way of the fight, and that police arrived within approximately five minutes of its start. Yorkside employees confirmed that the fight occurred, but did not have any details regarding what started the argument.

Gerald McElroy ’09 said he was seated in the section to the left of the door when a large crowd entered, filling the restaurant to capacity.

“All of a sudden we heard punches and screaming,” he said. “People in the restaurant didn’t know what to do, and were standing to the side and letting them fight it out until the police arrived.”

The fight soon developed into a spectacle, McElroy said, as people not caught in the middle stood on chairs to watch and take pictures. He also said he heard glass shattering, but was not sure of the source. There was no obvious damage to the restaurant on Sunday, and Yorkside employees working Sunday afternoon and evening said they were not aware of any damage.

Both Mittermeier and McElroy, as well a third witness, said the police defused the situation with the help of a chemical — possibly Mace, a type of tear gas. The fight had already started to die down by the time the NHPD arrived, McElroy said.

“Within five minutes the police came,” McElroy said. “All of a sudden I started coughing, and I didn’t know why until someone said [the police] had mace.”

McElroy said he had never seen Yorkside or the nearby area in as much of a chaotic state as he did then.

But Bevan Dowd ’08, who was near the door when the fight started, said she was not particularly shocked by the incident.

“It wasn’t as epic an ordeal as what people are saying,” she said. “I’m not very concerned. There were 10 police there within minutes of it happening.”

McElroy said the situation was likely exacerbated by the overcrowding of drunk people in the restaurant, a result of the limited number of places open to eat at that time of night.

Yale Police Department Sgt. Steven Woznyk has said the YPD often receive an increase in calls about disturbances as bars and clubs close and people filter onto the street and into nearby restaurants.