Beverly mansion burglar likely had ‘inside knowledge,’ experts say

An armed intruder burglarized this waterfront mansion at 34 Paine Ave. in Beverly and took off with valuable items. An investigation is ongoing. Pat Greenhouse/Globe Staff

In the mysterious weekend burglary of a historic Beverly mansion, experts say the initial facts suggest the perpetrator had inside knowledge of the sprawling seaside property, which sold in 2023 for almost $20 million.

The masked intruder broke into the house early Saturday morning, assaulted and tied up its sole occupant, snatched several valuable items, and fled in a stolen Porsche, according to police and the homeowner.

The case is currently being investigated by Beverly police, with assistance from Massachusetts state troopers and the FBI.

There are several strange circumstances investigators are likely probing, according to legal analysts and observers.

Whenever an extremely high-end property is robbed, there are generally two main reasons: Either the perpetrator targeted the home at random based on its apparent value, or “more likely, there’s some connection to the house,” said John Nardizzi, a private investigator based in Boston.

That could mean a staff member or anyone else with knowledge of daily routines, operations, or weaknesses in the security system. The connection “could be pretty attenuated,” Nardizzi added.

“Sometimes these people will come up with a sort of elaborate plan to target the property at a vulnerable time,” he said in a phone interview Tuesday.

In this case, the break-in occurred when the home’s caretaker was the only person there.

She was pistol-whipped, “forced to move through the house at gunpoint, and at times was dragged by her hair down staircases,” said the homeowner, Thomas J. Swan III, who spoke with the Globe on Monday. She was ultimately tied up in the garage by someone wearing a balaclava mask, he said.

Eventually, she unbound herself, ran to a neighbor’s house, and reported the crime to police, Swan said, referring to the woman as a family friend. He said she was shocked and traumatized from the experience.

Given how the robbery transpired, Swan said, “It was probably someone familiar with the house.”

Another puzzling aspect of the case: The thief stole a Porsche from the driveway to use as a getaway car. That also suggests “inside knowledge” of the property, Nardizzi said. But it raises obvious questions about how the person got there in the first place.

“Could somebody be so stupid as to take an Uber over there? Yes, it’s possible,” Nardizzi said.

Authorities ultimately recovered the stolen vehicle in Lynn, according to Beverly police spokesperson Sergeant Mike Boccuzzi.

Officials said the victim was transported to Beverly Hospital for treatment and later released. Beverly police declined to release additional details or updates Wednesday, including an initial police report.

“It’s not a routine residential nighttime burglary. This is an exclusive location; it’s difficult to get there by transit,” said David Sarni, a retired New York Police Department detective and adjunct professor at John Jay College of Criminal Justice.

“That’s a big house. You’d have to know what you’re looking for,” he said. “It’s almost like burglarizing an entire apartment building.”

To begin untangling the case, investigators would likely try to interview the caretaker right away, analysts said.

“That interview is extremely important,” Sarni said.

Even though she was injured, she would have to be eliminated as a suspect, as would Swan, said longtime Boston private investigator John DiNatale.

“The detectives should know this. Then it’s grunt work,” he said in a text message, adding that he would be surprised if the crime was random.

Detectives could conduct multiple interviews with the caretaker to uncover more details or potential inconsistencies. They could do a walkthrough of the house with her as well, which might lead to forensic evidence like fingerprints or DNA, experts said.

Investigators would likely inquire about schedules and daily routines, people with access to the property, recent visitors, security systems, cameras, and more.

“You always have to look internally before you do anything else,” said Bob Long, a retired investigator and security consultant. If there’s video surveillance, he said, that could shed significant light on what happened.

Detectives would also want to know exactly what was stolen, experts said. Things like jewelry or watches are easy to resell, but unique items like original artwork could pose bigger challenges.

Swan, the homeowner, said the items were extremely valuable, but declined to specify what was taken. He said he was limited in commenting due to the ongoing investigation.

A business lawyer and investment banker who co-runs The Swan Group, Swan purchased the luxury property for $18.275 million.

Named “Rock Edge,” the historic Georgian-revival style mansion sits perched atop a bluff overlooking the ocean. It was commissioned in the early 1900s by a woman named Marian Sargent, a descendant of Thomas Jefferson whose late husband had made a fortune in the textile industry. She used the three-story, 17-room house to escape her winter residence in Boston, records show.

A Facebook account under Swan’s name includes a 2023 post about moving to Rock Edge, saying his young children were “over the moon” when they saw it.

“It’s literally and figuratively a new beginning,” the post said, along with a photo of Swan and the children smiling on the property’s private beach. “I am so grateful and I have complete faith that the best is yet to come.”

The mansion is among many stately homes lining Paine Avenue, a seaside neighborhood in a particularly wealthy corner of Beverly known as Prides Crossing. Neighbors said many residents spend the winters elsewhere in second or third homes. But they said staff — cleaners, landscapers, personal chefs, builders — are often coming and going year-round.