FALMOUTH – Descendants of a War of 1812 veteran believe a vacant, ramshackle house that was built earlier this century may be on top of his grave.

But a previous owner says the property, situated on a potentially valuable piece of commercial real estate, has no grave of Capt. William Crabtree or his family.

Crabtree, a Portland merchant and shipbuilder, served as a private during the Revolutionary War and was captain of a brig that captured at least three British ships during the War of 1812.

In 1815, Crabtree retired and moved to a 150-acre farm in west Falmouth. He died in 1843 at age 83 and was buried in a family cemetery. For decades, nobody has been able to find the graveyard.

Greg Poulos of Falmouth, the great-great-great-grandson of Crabtree, has been searching for the cemetery. Five years ago, he was told by an elderly woman named Elsie Conant that it was under her house.

Conant, who has since died, said her husband had built the house in the early 1930s after the family’s old house burned down. The property was part of her father’s dairy farm, which was the former Crabtree farm.

The lot, later owned by Arthur McLeod of Yarmouth, is now owned by David Chase, a Falmouth builder.

Chase said he was flabbergasted to hear graves may be under the small, ramshackle house. He said he doesn’t how to verify the descendants’ claims, but he has no intention of disturbing the dead.

“There are lines I don’t cross in the effort to make money and that is one of them,” Chase said.

McLeod said Chase has nothing to worry about. McLeod said Elsie Conant had told him that the bodies in the cemetery were moved to another location, but he doesn’t know where.

“Nobody is buried under the house,” McLeod said.

State law prohibits construction within 25 feet of a known cemetery, whether the graveyard is properly recorded in the deed. If the burial site is undocumented, the owner who wants to build on it must pay to determine the existence and location of any graves.

Grave site or not, the lot is in a commercially strategic area. It’s near the Maine Turnpike and a new supermarket, and is next door to a parking lot for BankNorth. The property is zoned to allow office and retail use.