The bodies of up to 50 migrants found in truck in Austria

The truck in which the horrific discovery was made

At least 20 migrants have been found dead in a lorry in Austria and some local estimates say that there could be up to 50 bodies in the vehicle.

Austrian police said the bodies were discovered on a road leading from the Hungarian border.

The lorry was parked on the hard shoulder of the highway.

Just drove past truck on A4 in Austria with 50 dead refugees inside. Terrible smell of death as we passed. pic.twitter.com/a2AiDnsy5V

— Lindsey Hilsum (@lindseyhilsum) August 27, 2015

Police believe the victims had been dead for some time, telling state broadcaster ORF that the bodies appeared partially decomposed.

Burgenland province police chief Peter Doskozil said the lorry, which had Hungarian licence plates, was apparently abandoned on Wednesday and its back door was left open, exposing the bodies.

He said the state of the bodies made it difficult to say how many there were in the lorry but estimated it could be up to 50.