RIVERDALE (CBS) — The search was on Saturday for a rapist suspected in at least two separate attacks on three young women in the past month.

As CBS 2’s Susanna Song reports, the most recent assault happened Thursday night in suburban Riverdale.

Police have released a sketch of the suspect, described as an African-American man in his mid-20’s, about 5-foot-8, wearing dark clothes and having a mustache.

In both attacks, the suspect was armed with a handgun and preyed on women as they waited for a bus or walked home from a bus stop, according to police.

On Saturday, community members walked door-to-door, passing out a sketch of the suspect, asking neighbors to report anything suspicious they’ve seen.

Community activists Dawn Valenti and Andrew Holmes helped alert neighbors about a disturbing development.

“I believe it’s a serial rapist, because it’s the same height, just about similar description,” Holmes said.

Police believe the suspect attacked two 17-year-old girls as they left a Pace bus stop on Halsted Street and walked to their homes a few blocks away Thursday night.

“The person walks up behind them, put a gun on them, forces them into a back yard and sexually assaults them and takes off,” Holmes said.

The victims reported the rapes happened in an alley near where Eileen Chmielewski’s mother lives by herself.

Chmielewski said she grew up in Riverdale.

“Absolutely; had a great childhood. You know, we didn’t have to to be afraid of anything,” Chmielewski said. “Never. You know, things have changed over the past, quite a few years and it’s scary to think that, you know, your mom is here.”

Holmes said it appears “there may be a connection” between the latest attack and another last month, when a woman reported she was attacked in the area.

Her description of the suspect, according to police, matches the sketch of the suspect in the latest attack.

“You try to be careful of your surroundings but you just never know,” one woman who lives in Riverdale said.

One neighbor at a time, leads have been coming in.

“One gentleman at the end of the block seemed to have some information to give us that we’re gonna pass along to the Riverdale Police Department,” Valenti said. “That’s a real good sign.”

There were also two sexual assaults late last month, a few miles away from Riverdale.

The suspect’s description in those cases is similar to the latest attack, but police are not saying yet if they’re linked.

Anyone with information should call Riverdale police at (708) 841-2203.

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