CHICAGO (CBS) — Three teens have been charged in the mob attack earlier this week that left two people badly injured earlier this week at Chicago and Wabash avenues.

Marcus Clark, 18, of the 500 block of East Bowen Avenue, and Keith Alexander, 18, are each charged with one count of robbery and two counts of aggravated battery in a public place, both felonies. Clark is being held on $300,000 bond; Alexander on $250,000 bond.

A third suspect, a 16-year-old boy, is charged with one count each of robbery and mob action, and two counts of misdemeanor battery.

The incident happened around 8 p.m. Tuesday. At the time of the attack, restaurants were packed with customers, and the nearby Magnificent Mile bustled with shoppers and people trying to get home.

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

One of the victims, who were also teenage boys, had been chasing the group after they had stolen his wallet, and was beaten to the point where witnesses said he had blood on his face and teeth knocked out.

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,” Bynum said Tuesday. “They really started fighting at the beach, then they started fighting in front of the Armani store, and again in front of Potbelly’s.”

The incident was one of several high-profile mob attacks that have happened in the past week, largely in the Gold Coast, Streeterville, and other busy and fashionable areas of the Near North Side.

On Saturday, two men were attacked in Streeterville. Three teens have been charged in the attacks against the men, one of whom was parking his scooter in the 300 block of East Chicago Avenue, the other of whom was assaulted while riding his bicycle at Lake Shore Drive and Huron Street.

On Wednesday afternoon, a man was attacked and robbed on the CTA Brown Line near the Chicago Avenue/Franklin Street stop. He was hospitalized and lost his wallet and iPhone.

On Wednesday evening, a woman was attacked and robbed at the Sheridan Road CTA Red Line ‘L’ stop, while carrying her 2-year-old daughter. Two suspects pushed the woman and her daughter down a flight of stairs.

Early Thursday morning, Jesse Andersen, the brother of Smashing Pumpkins frontman Billy Corgan, was attacked on the CTA Red Line as he went to work. One of the suspects, a female, took Andersen’s iPod and when he tried to grab it back from her, he was “blocked” by other suspects and then punched in the mouth, authorities said.

Two attacks have also occurred on the city’s Near West Side, one of them on a CTA bus. Both the victims in those cases were University of Illinois at Chicago students.

Police have stepped up patrols since the attacks, particularly around the Magnificent Mile and Streeterville.

The Sun-Times Media Wire contributed to this report.

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