Boston Police want to talk to the man in new surveillance video, appearing to prowl around the outside of a home in South Boston.
Someone has been sneaking through open windows while the victims sleep, stealing their belongings in at least five breaking and entering cases this week.
NBC Boston spoke with one of the victims, who says Monday morning the burglar climbed though a first floor window and stole his watch and money while his family slept upstairs.
"I was up until 1 o'clock in the morning reading, and so I know it happened sometime between 1 and 6:30 in the morning," said John McGahan.
He says he left the downstairs window open about two inches.
"It's sad you have to do that on a summer night, but we'll take the necessary precautions to ensure this doesn't happen again," he said.
Another victim posted on Facebook that the burglar actually dragged furniture into a garden and climbed up through a second floor window.
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Police are asking people to keep their doors and windows locked.
The break-ins happened in the areas of Gates and Frederick streets, and also in the areas of Mercer, Old Harbor and East Seventh streets.
Boston Police say anyone with information is urged to call 617-343-4742.
Anonymous tips can be made to 1-800-494-TIPS. You can also text the word "Tip" to CRIME (27463).