Why is there a dark helicopter flying low above Boston?

A low-flying helicopter has been stopping people in their tracks in and around Boston. The dark, unmarked helicopter is hovering low over city neighborhoods and intersections, not far from some neighbors' windows.

"Just above the trees, and you can see in the video where the trees were swaying and everything," said Rich Gurska, one of many who shared photos and videos across social media. "Just a short time ago I looked back and it was over 700 views."

And as work brought him across the city, from downtown to Jamaica Plain. He just kept seeing it.

"I just held the shot for a little bit and then I edited it later and I put the music in from 'Goodfellas' where Henry Hill was all crazy about the helicopters," said Gurska. "It just reminded me of that."

Although it is not a surveillance chopper like that infamous scene from the movie, Boston Police posted about it, advising neighbors of routine electrical powerline inspections between Hyde Park and Logan Airport.

"I wasn't too concerned. I knew something had to be going on and since there was no police presence on the ground it couldn't have been serious," Gurska said.

Police explained that the "planned, authorized utility inspection operation" would happen during business hours over several days.

While many on the ground might be distracted by the photographer seemingly hanging out its side, his focus is apparently on the towers of a transmission line corridor running throughout Boston. Police say there is no cause for concern.