By Mai Martinez

(CBS) – A warning for parents on the North Side: A man is exposing himself to young girls, Chicago police say.

Four incidents happened within a few blocks of each other last month in the Albany Park Police District.

There are three schools in this immediate area.

News of the disturbing incidents was top of mind for parents and students.

Jane McKay, like many parents of students at Albany Park Multicultural Academy and Edison Regional Gifted Center, was disturbed to learn two girls –ages 13 and 14– were recently approached by a man in a vehicle while walking home from school.

Chicago police say the man called the girls over, then exposed and inappropriately touched himself in front of them.

“It’s probably something he’s been doing for a long time, so I think he obviously needs some help,” McKay says.

Chicago police say the first incident happened in the 4800 block of North Sacramento on May 8. The second incident was in the 3600 block of West Ainslie on May 22.

Then, on May 26 in the 4100 block of North Richmond, a man in a red or burgundy van called an 11-year-old girl over but she ran away and reported him.

Later that same day, in the 4300 block of North Spaulding, a 30-year-old woman said around 9:40 p.m., a man approached her from behind and touched her midsection. He ran off when she confronted him.

Back at the schools, parents say they’re reminding their children and each other to be alert.

Police are looking into the possibility that all four incidents might be related. Anyone with information is asked to call Area North Detectives.