A woman walking her dog Wednesday night in Arlington Center spotted a man who appeared to be masturbating near the Town Hall flagpole, at the corner of Massachusetts Avenue and Academy Street.

The woman told Arlington Police Thursday morning that she heard the man masturbating in one of the bushes near the flagpole at about 8:30 p.m. but did not see his privates.

The man then approached her as she continued to walk away from Massachusetts Avenue on Academy Street, she said, and he began making sexually-suggestive comments about her body and about what he had just done.

The woman said she began to hurry toward Maple Street, and that’s when the man took off down Massachusetts Avenue, toward Arlington Heights.

She said the man spoke to her for less than 20 seconds. She described him as a white male, who was about 50 years old, 5 feet 10 inches and 150 pounds. He was wearing a gray T-shirt and tan shorts, she said.

On Sunday evening, a Medford woman called police after seeing a man who appeared to be masturbating on the Arlington side of Lower Mystic Lake.