CHICAGO (CBS) — A warning for women in the Greater Grand Crossing neighborhood: Police believe the same man is threatening women at gunpoint, sexually assaulting them, and robbing them.

Police said one man is behind four attacks in just over a month.

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In all four assaults, the man approached lone women, lured them to a secluded area, pulled out a gun, sexually assaulted them, and stole their property.

The attacks happened:

• around 5 a.m. on July 12 near 76th and Evans;
• around 5:30 a.m. on July 25 near 74th and Vernon;
• around midnight on Aug. 6 near 74th and King;
• around 2 p.m. on Aug. 23 near 77th and Langley.

Community activist Andrew Holmes said the suspect likely lives near the places where he’s committed the crimes.

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“He’s very disturbed, and he needs to be apprehended,” Holmes said.

Police have only a vague description of the suspect, who was last seen near 67th and Prairie.

Some women in the area said they are now being extra cautious, and are no longer walking outside alone.

“When you’re walking down a block, a city block, just make sure that you’re aware of abandoned buildings that may be on the left or right of you. If you’re getting close to the corner or the alley, slow down, take a look behind you. Make sure nobody is lurking in them bushes, or especially in them alleys,” Holmes said.

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Anyone with information on any of the attacks should call Area Central detectives at 312-747-8380.