Narrative:

An aircraft (twin cessna) with an engine out landed on runway 20C and cleared the runway. An airport vehicle without authority/authorized was proceeding on the runway opposite direction to landing traffic, a lifeguard twin cessna. There was time and I issued the lifeguard to be prepared for a possible go around. I advised ground to get the vehicle off the runway. The vehicle cleared before the aircraft crossed the landing threshold and I let the aircraft land.

Google
 

Original NASA ASRS Text

Title: A TWIN CESSNA PLT, ON FINAL TO BNA, WAS INFORMED OF A POSSIBLE GAR DUE TO AN ARPT VEHICLE BEING ON THE RWY.

Narrative: AN ACFT (TWIN CESSNA) WITH AN ENG OUT LANDED ON RWY 20C AND CLRED THE RWY. AN ARPT VEHICLE WITHOUT AUTH WAS PROCEEDING ON THE RWY OPPOSITE DIRECTION TO LNDG TFC, A LIFEGUARD TWIN CESSNA. THERE WAS TIME AND I ISSUED THE LIFEGUARD TO BE PREPARED FOR A POSSIBLE GO AROUND. I ADVISED GND TO GET THE VEHICLE OFF THE RWY. THE VEHICLE CLRED BEFORE THE ACFT CROSSED THE LNDG THRESHOLD AND I LET THE ACFT LAND.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.