By Kristen Johanson

CHESTER COUNTY, Pa. (CBS) — The area known as Duffy’s Cut is a mass grave, along the Main Line, where 57 Irish immigrant railroad workers are buried. They were killed in 1832 by a mob of local vigilantes during the height of the cholera epidemic.

“They were poor. They were Catholic, at a time when Catholics weren’t welcomed,” says Dr. Bill Watson, a history professor at Immaculata College, and Director of the Duffy’s Cut site. “They were suspected of undercutting local laborers at a cheaper rate for the work for the railroad. All of this lead to resentment and distrust.”

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Brothers Work To Recover The Rest Of Duffy's Cut Remains

Workers survey ground Friday morning at the Duffy’s Cut mass grave cite. (Credit: Walt Hunter)

Watson says the workers were recent immigrants, hailing counties Donegal, Tyrone and Derry in Ireland, and he says they were considered expendable.

“They were all victims of violence, recent blows to head of each of them, signifying that they were struck over the head with sharp implements and one guy even had a bullet in his head,” says Watson.

A few years ago, remains from seven of the bodies were unearthed and reburied in proper ceremonies. Now, Watson and his brother Frank are working to unearth the rest.

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“If we can find these bodies, and we can prove that like the first seven, the rest of them were murdered, this very well could be the worst mass murder in Pennsylvania history,” he said.

The grave lays about 60 feet from the Amtrak rail line, right in the heart of Chester County.

The Watson brothers have gotten final approval from Amtrak and will begin their search for the bodies on Friday, starting with radar and a survey of the area.

Alongside an archeology team from the University of Pennsylvania, they will take core samples of the earth, before digging in. The effort will take time and money.

“It’s a kind of crusade for us, an obsession,” says Watson. “Something we have got to see through to conclusion.”

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