PORTLAND – A wave of vandalism has caused thousands of dollars in damage at businesses in the city’s Old Port shopping and entertainment district during the past two months.

The damage has been linked to a series of late-night episodes that resulted in broken windows at several storefronts.

Merchants were to meet with Portland police on Wednesday to explore strategies for putting a stop to the problem.

In recent years, Old Port business owners have periodically asked for additional police attention in the area. Most recently, the department has provided extra officers on an overtime basis to counter the appearance of rival motorcycle clubs.

Police have not determined who is responsible for the vandalism, but some merchants’ concerns have focused on parks that serve as popular youth hangouts.

The Parks and Recreation Department has reported thousands of dollars in damage to the parks themselves from damaged benches to pried-up bricks from the walkways.

The vandalism has become a costly frustration for some business owners.

“I wanted to cry,” said Joseph Palacci, owner of the electronics store Pierre’s of Exchange Street, when he discovered the plate glass window on his storefront had been smashed. “I was depressed, because it was expensive.”

Palacci had his windows broken twice in three days in May. Windows also have been broken at Natasha’s restaurant and Stein Glass Gallery, where a $5,000 glass sculpture was also destroyed.

A fire was set in the doorway alcove of Amaryllis Clothing. Damage also has been reported at Java Net and the Golden Giraffe.

“All these businesses feel they are being harassed and threatened and are unable to do business,” said Portland Police Chief Michael Chitwood. His department is willing to work with merchants and others, he said, but wants to hear from the City Council and social service providers before taking any action.