HERNANDO (AP) — Two shooting victims along Mississippi highways may have been killed by someone who posed as law enforcement and pulled them over late at night, authorities said Monday.

Investigators were not releasing many details, including whether they believe a single gunman is responsible or what type of weapon was used, said DeSoto County district attorney John Champion. Champion said the shootings are related, but there’s no evidence to suggest that the victims knew each other.

“We do not have any witnesses at this point,” Champion said. “We’re asking the community for help.”

Thomas Schlender, 74, of Raymond, Neb., was found in his car on Interstate 55 in Panola County on May 8 about 1:30 a.m. Three days later, Lori Anne Carswell, 48, of Hernando, was found near her car on Mississippi Highway 713 in nearby Tunica County about 2:15 a.m.

Carswell just left work from Fitzgerald’s Casino, also known as the Fitz Casino, in Tunica County, Champion said.

The interstate is more heavily traveled than the state highway where Carswell was found, but both areas are low-lying along the river with plenty of open fields in the northern part of the state. Authorities were investigating whether the suspect was impersonating an officer and that is how the people ended up on the side of the road, said Mississippi Bureau of Investigation director Larry Waggoner.