A post-mortem examination has revealed the remains of a baby found on the side of a motorway had been used as part of a medical exhibit.
A lorry driver who broke down on the M25 near Potters Bar, Hertfordshire, found the remains on the side of the carriageway on Tuesday.
A police spokesman said tests found the foetus was preserved and aged between 14 and 16 weeks old.
Police are no longer treating the case as suspicious.
A police spokesman said: "It was a foetus of between 14 and 16 weeks gestation and had been preserved some years ago so there will be no appeal."
The post-mortem examination was carried out at the Great Ormond Street Hospital.
Police said they did not know how the remains had come to be at the side of the eastbound carriageway of the motorway, but were not planning any further action.