BELLEVILLE, N.J. (CBSNewYork) – The basement of a church built in 1725 is now the talk of the town in Belleville, New Jersey.

Graves were discovered under the foundation and now specialists are using modern technology to unlock the mysteries of the past.

READ MORE: Protesters Attempt To Storm Entrance Of Barclays Center Over Nets' Refusal To Allow Kyrie Irving To Play Due To NYC Vaccine Mandate

The Reformed Church of Belleville, established in 1697, is steeped in history – especially from the Revolutionary War era.

Scientists probe the basement in the Reformed Church of Belleville in New Jersey. (Credit: CBS2)

Under the church yard headstones and far below the stained glass inside this landmark there was even more history hidden.

Township of Belleville Mayor Michael Melham took CBS2 down to where the passage gets narrow and the headroom slight – to meet the researchers from Rutgers University who are looking for remains in unmarked graves.

“During a construction project here several years back there were actually human remains that were found,” Mayor Melham said.

Historians believe they were Chinese immigrants from more than 150 years ago, many of them railroad workers.

A memorial to them was constructed, but to get a handle on how many unknown graves are there means grabbing the handles of radar machines to scan deep down.

A memorial has been placed at the Reformed Church of Belleville for the unmarked graves. (Credit: CBS2)

Revealed were mysterious sections that appear to be several feet long.

READ MORE: NYPD: Knife Fight Spills Into Midtown Pizzeria, 2 Taken Into Custody

“Partly archaeology, partly forensics, we do this when we get asked as kind of a community service project,” Lee Slater, a geophysics professor at Rutgers said.

The team members say maybe you’ve seen a movie with the same technology that peers in to show a skeleton or something very specific, but they say it doesn’t work that way.

A shadow on the screen can point the way. The search here is taking place indoors and out.

“We can create this contour heat map where it shows oh there are those hotspots,” Joshua Thompson, a PHD student at Rutgers said.

“We tell them if there are some interesting features that might be worth excavating,” Prof. Slater added.

CBS2’s Dave Carlin walks through the narrow passages inside the Reformed Church of Belleville in New Jersey. (Credit: CBS2)

Church owner and Pastor Mike Ortiz said finding one unmarked grave here meant they had to keep looking.

“Whatever they find is part of history,” Ortiz said. “I think it’s very important not to forget about them.”

The spiritual and the scientific mix so mysteries get solved – with no stone unturned.

MORE NEWS: With Less Than A Week Before NYC's Deadline, Municipal Workers Hold Anti-Vaccine Mandate Rally On Staten Island

Once remains are found, a decision will be made on whether to relocate them or leave them where they are.