Police investigators say the bodies of three elderly people killed in a road accident could have remained undiscovered for several days.
A lorry driver noticed a car in a ditch on the A1 near Grantham, Lincolnshire, on the afternoon of Christmas Eve.
The three victims in the car - two men and a woman - were all in their 80s and from Doncaster in South Yorkshire.
Police are not releasing their identities until their next of kin have been informed.
The lorry driver who found the Rover 214 said the vehicle was cold and the car was only visible because of the height of his cab.
The accident brings the number of people killed on Lincolnshire's roads so far this year to 100, compared with 93 in 2002, 88 in 2001, 72 in 2000 and 104 in 1999.
Inquiries are continuing to establish exactly when the accident happened.