Ten to 12 doors in downtown Arlington Heights have been painted with graffiti in the past two weeks, police said.

The vandals have targeted rear doors in secluded alleys on weekends or other times the stores are closed, said Sgt. Tom Seleski.

"It's definitely not gang-related," he said, adding the tags are in the style of bubble letters but that no words can be deciphered.

Both rows of stores in Evergreen Shopping Center north of Sigwalt Street between Evergreen and Dunton avenues were hit. Other occurrences were on Dunton and Campbell Street in the same area.

At one time, three teens were observed spray-painting a door, but no arrests have been made.

"Crimes like this diminish the aesthetics of the downtown," said David Becker, president of the Arlington Heights Chamber of Commerce.

"It sets the wrong tone, and people who might not be familiar with the downtown and what Arlington Heights stands for as a vibrant community can get the wrong idea," said Becker, owner of Fastsigns of Arlington Heights.

Property owners have had to spent time and effort to remove or cover the graffiti, then remain vigilant against it happening again, he said.

Graffiti is criminal damage to property, said Seleski. Owners are required to remove or paint over the tagging immediately.

It has been at least a year since graffiti has been a problem in downtown Arlington Heights, he said.

Anyone with information is urged to call Arlington Heights police or for anonymity and a possible reward call Arlington Heights Crime Stoppers at (847) 590-7867.