The unidentified resident called police around 1 a.m. Monday to report he had hit the man with a bat after telling them he found the man, dressed all in black, crouched behind a wall, said Sgt. Robert Shawinsky.
The resident, concerned about recent car break-ins in the area, told police that he was "sleeping lightly" in the event someone tried to break into his vehicle, Shawinsky said.
Just before 1 a.m., the man said he heard something and went outside armed with a wooden baseball bat in the area of Hope Street, he added.
That's when the resident said he found the man crouched behind a wall. He told officers he began to yell and that the man stood up with a knife in his hand, so he swung and hit him in the back of his head, Shawinsky said.
"We aren't sure if the person was hit or not," Shawinsky said. "We didn't have a report of anyone going to the hospital."
Police and a New Canaan Police K-9 dog looked around the area, but no suspect was found.
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