Twin 72-year-old sisters were found murdered yesterday at their rural Virginia home, about 20 miles south of Fredericksburg, according to state police.

The bodies of the two widows, identified as Martha Corker and Mary Carneal, were discovered by their brother, John Acors, authorities said. Caroline County Sheriff Ottie Moore said Acors telephone police shortly before 11 a.m. to report finding his sisters dead.

First Sgt. C. R. Deavers, who is overseeing the state police investigation, said the motive for the killings is unknown. He declined to make public further details about the incident, saying these might jeopardize the investigation. Autopsies are scheduled to be conducted by the medical examiner's office in Richmond, Deavers said.

The two women lived in a small frame house off U.S. Rte. 1 near the Golansville community, authorities said.

Police cordoned off the house and did not allow newsmen inside. Reporters who visited the area quoted neighbors and relatives as saying the two women last had been seen in church on Sunday.

One member of the victims' family was quoted as saying, "There was blood all over the house." One of the sisters' bodies reportedly was found on the kitchen floor and the other in bed.

Authorities declined to confirm the descriptions of the murder scene.