UPDATED 06/08/11 8:06 a.m.

CHICAGO (CBS) — Three people are now in custody in connection with another mob attack, in a trend that is becoming all too familiar in Chicago.

As CBS 2’s Kristyn Hartman and Susanna Song report, the latest incident happened around 8 p.m. Tuesday at Chicago and Wabash avenues, a busy and packed area just a few blocks from where the other high-profile incidents occurred.

Police responded to a call of a battery in progress shortly after the incident.

At the time of the attack, nearby restaurants were packed with customers, and the nearby Magnificent Mile bustled with shoppers and people trying to get home. But something seemed to be amiss when a group of teens were spotted running toward the entrance to the Red Line subway.

“I just saw a whole bunch of kids run all over the place; I would say probably about 20,” said valet employee Steve Galarza.

Witnesses believe the attacks began on the lakefront around the Oak Street Beach, then continued west several blocks.

Police say it all started one of the two victims pulled out his wallet to buy a single cigarette from a teen in the mob, when another teen swiped the victim’s wallet and the mob began to run.

It was after the victims had caught up with the group that the mob knocked the pair to the ground and began to beat them.

LISTEN: Newsradio 780’s Bernie Tafoya reports

Corey Bynum witnessed was working at Ghirardelli Chocolate, 830 N. Michigan Ave., when he saw the roving group of teens.

“I find it really miraculous that the two kids got up and chased them again, because according to the victims, it happened at the beach,” he said. “They really started fighting at the beach, then they started fighting in front of the Armani store, and again in front of Potbelly’s.”

Bynum quickly stepped in.

“I immediately dropped my things after I found out what was going on, and ran to go help,” Bynum told WBBM Newsradio 780’s Lisa Fielding.

LISTEN: Newsradio 780’s Lisa Fielding reports

Bynum said he got the full story of what happened from an injured victim.

“The victim that they jumped on, I went to go help; we picked him up and talked to him to find out if everything was OK, and he told us everything that happened,” Bynum said.

The mob got away with a wallet and about $350, and most of the offenders escaped. But three teens – one of them a 16-year-old boy and two of them 18-year-old men – were arrested.

“I saw a couple guys who looked pretty hurt; pretty beat up, some blood on their face. One of the guys had a couple of teeth knocked out; freaking out, calling people, and then a bunch of squad cars; ambulances came, and they started trying to ID some of the guys,” said witness Austin Gorvett. “I saw a couple of guys get arrested.”

Gorvett called the incident upsetting, “but unfortunately, not surprising; so much of this has been happening lately.”

Bynum says there were dozens of people around during the incident, but no one stepped in to help.

“The fact that it happened in front of a store – Potbelly’s – and no one actually did anything, was just sad,” he said.

In addition to increased police patrols, the Guardian Angels say they will also be patrolling the Gold Coast in Streeterville to help police maintain control of the area.

No charges had been filed against the three teens as of the early morning hours.

The Sun-Times Media Wire contributed to this report.

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