EAST RIDGE, Tennessee -- A manhunt is underway for a 23-year-old man suspected of killing his mother and friend, then confessing to the crimes on Facebook.The two victims are the suspect's mother, Vi Lawhorn, and a friend.East Ridge Police confirmed to WTVC that Mississippi Highway Patrol located Casey Lawhorn's vehicle in Jasper County, Mississippi, around 7 p.m. Sunday.Casey Lawhorn was not in the vehicle, police said.This comes after Casey's brother told WTVC that he had learned Casey was traveling southbound on I-59 through Mississippi.The name of the friend has not yet been released as the next of kin has not been notified.He is still believed to be driving a gold Ford Taurus with Tennessee license tag W0327L.Casey Lawhorn is considered armed and dangerous.