CHICAGO (CBS) — Police have issued a community alert for people who ride the CTA Green Line on the South Side.

As WBBM Newsradio’s Bernie Tafoya reports, police say thugs have confronted riders on the line in recent weeks, on the trains between 47th and 51st streets.

“What they’re doing is they’re attacking the individual – holding him – while the other individuals go through their pockets – take cell phones, money, anything of value, jackets—and then they push the CTA passenger off the train, where they’re telling them, ‘This is your stop, and we stay on the train,’” said Miguel Fuentes, head of the Guardian Angels anti-crime group.

LISTEN: WBBM Newsradio’s Bernie Tafoya reports

Police said in a community alert that a 17-year-old boy was attacked on the Green Line at 51st Street around 11:20 a.m. Jan. 5, and threatened to beat him up if he didn’t give them his jacket and cell phone. The boy surrendered his valuables and got off the train.

“If I didn’t give it to them, they were threatening to jump me on the train, and so I was more concerned for my life than anything so I just gave the stuff up then,” the victim, honors student Marcus Powell, told CBS 2’s Mai Martinez.

Around 5:25 a.m. Feb. 5, three men came up to a 23-year-old man at the 47th Street stop. One grabbed him by the throat while two others searched his pockets and took his cell phone, then pushed him out onto the platform while they remained on the train, the alert said.

Commuters are frustrated by the incidents.

“I think it’s ridiculous that you can’t go to work or wherever you’re going without being assaulted,” said Green Line commuter Lisa Stroud.

CTA President Forrest Claypool said Monday that police are stepping up patrols and focusing on “hot spots” of crime because of the robberies.

“Security continues to be our number one priority. And I think the steps we’ve taken reflect that,” he said.

The suspects are described as two or three African-American males between the ages of 16 and 21, standing between 5 feet 10 and 6 feet 2 inches tall and weighing between 190 and 230 ponds.

The Guardian Angels say they will be patrolling the Chicago Transit Authority line on the South Side, and are prepared to make citizen’s arrests if they see a crime committed.

Anyone with information about the robberies is asked to call Wentworth Area police detectives, at (312) 747-8382.

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