A purported ghost sighting in an area Market Basket grocery store last month took the region by storm. It started with a tweet and quickly went viral. If you came across that story online or in the press, maybe you laughed it off — or scoffed. Perhaps you posted about it on social media — all in good fun, of course. Heck, you might have even chatted with friends about whether you think ghosts are actually real.

Winthrop's Ellen McNeil went to work.

"I did get in touch with Market Basket and I said, 'If you want a real team to come in and check the place out, I’d be happy to,'" said McNeil, founder of SPIRITS of New England — a locally-based paranormal team that’s been investigating hauntings since 2009.

"If you’ve never had a paranormal experience, It’s very easy to judge people who have," she said. "It didn’t happen to you. So who are you to judge me?"

McNeil, it turns out, is far from alone. The website Paranormal Societies lists more than 90 paranormal organizations operating here in the Bay State — and dozens more throughout New England.

Waltham’s Tom Elliott is founder and director of Boston Paranormal Investigators.

"We have a core group of about 20 people," he explained. "On any one investigation, there will probably be like 10-12 people going out."

Elliott likens Boston Paranormal Investigators to the ghost hunters you’d see on TV. In addition to his core group, he counts 400 more members who subscribe to his mailing list.

If it all sounds incredulous, consider that a 2009 YouGov survey found that 45 percent of Americans believe in ghosts. A 2016 study from Kansas State University concluded that belief in the paranormal has been on the rise for two decades — and is likely to continue to rise. In other words, there’s a market.

"I’m not here to convince anyone. I’m not on a crusade. I’m just here to help people," said Medfield’s Anthony Duda, who has been investigating the paranormal for 40 years.

Duda works mainly one-on-one with people who believe their homes may be haunted. He doesn’t charge for his services, and he said he chooses his clients carefully. Duda said that when he takes up a case he enters the space, searches for ghosts or spirits, communicates with them, and — if necessary — eradicates them.

To aid in this task, Duda has amassed an impressive collection of gear — from multi-spectrum cameras to sensors to sensitive microphones — much of it custom built. He believes he has captured both images and audio of ghosts, and said he’s seen things that would make a believer out of anyone.

"We were setting up equipment," he said, recounting a particularly memorable experience, "and all of a sudden this woman was picked up — like a foot off the ground — and she was thrown on the bed."

Of course, not everyone buys the idea that the dead are still among us.

"I was all in. I though they were real," said former ghost hunter Kenny Biddle. "I thought that little white smoky things in photographs were ghosts. I thought they made noises. I thought they could talk to you. I was a full believer."

Today, Biddle writes for Skeptical Inquirer Magazine, essentially investigating the claims of paranormal investigators from a scientific perspective.

"The more I learned about the scientific process and how to control experiments and how to control the environment, I realized that most of these anomalies were caused by either me or other people in the environment," he explained.

Biddle says he believes most paranormal investigators really are sincere in their beliefs, and in their desire to help. He does, however, worry about vulnerable people being taken advantage of. He has two pieces of advice for those who have hired — or are inclined to hire — a paranormal investigator: Never stop learning, and ask, "How do you know that?"

Duda agrees that those who believe they are experiencing the paranormal should proceed with caution. He says there are plenty of ghost hunters out there who do things — as he puts it — "the wrong way."

"If you go in and you say — and a kid hears this — 'Mr. and Mrs. Smith, you have a demon in your home,' you're gonna send somebody over the edge. And you're responsible for that," he said. "So you better — when you walk into that home — you better know what you are doing."

As for the skepticism?

"If somebody wants to believe I’m nuts, maybe I am. I mean, I don’t care," said Duda. "There’s nothing abnormal about the paranormal. We just don’t understand it yet."

So, the next time you hear about some haunted encounter, keep in mind that whether or not the ghosts are real — in this region — the paranormal investigators undoubtedly are.