LOUISVILLE, Ky. (WDRB) -- Police investigating the murder of a mother and daughter in Nelson County say they now know for certain that at least one person inside a black Impala captured on surveillance video was involved in the murders.

last month.

A week after the victims were found, police released surveillance video showing a black Chevrolet Impala. Now investigators tell us they know for sure that one person in the Impala -- believed to be a 2012 or 2013 model -- had something to do with the murders.

The video images of the Impala appear to have been captured from cameras at a gas station.

"We've gone out and looked at all those cars, but if the car came from Washington County, or another county, then we're still searching for that car and haven't located it, so we do believe that someone in the public can help us tremendously limit our search looking for that car," said Kentucky State Police Lt. Jeremy Thompson.

Lt. Thompson says investigators have checked at least 90 black Impalas in Nelson County but haven't found the car seen in the video. They are asking anyone with information to come forward and let police know who owns the car.

Anyone with information should call Kentucky State Police Post 4 in Elizabethtown at

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