A 28-year-old man was charged Tuesday with killing a couple who traveled to rural Georgia seeking to buy a 1966 Ford Mustang through an advertisement placed on Craigslist, an online classified ad service.

Investigators accuse Ronnie Adrian "Jay" Towns, 28, of McRae, of killing 69-year-old Elrey "Bud" Runion and his 66-year-old wife, June Runion of Marietta. They were found dead Monday, shot in the head. Towns did not enter a plea Tuesday during a brief court appearance, and his attorney declined to comment.

Telfair County Sheriff Chris Steverson said robbery appears to have been the motive, though he declined to discuss many aspects of the ongoing investigation. Authorities said there's no evidence Towns owned the sort of classic car that the Runions wanted to buy.

The Runions' death represents the latest case in which people responding to online advertisements have been victimized.

Others include:

— A newlywed couple in Pennsylvania pleaded guilty in August to murder in the stabbing death of a stranger they lured through a Craigslist ad offering companionship.

— Authorities charged two reputed gang members in Los Angeles with robbing and killing a man who police say was lured to his death with a Craigslist ad and gunned down on Oct. 19, 2013, in front of his 15-year-old son.

— Two men have been charged in the October 2013 shooting death of a South Carolina man selling his pickup on Craigslist, authorities said.

— A self-styled street preacher in Ohio was sentenced to death in April 2013 after being convicted of murdering three down-and-out men lured by bogus job offers posted on Craigslist.