At least seven farm workers, including three women from Tamil Nadu, were killed and 12 others injured on Sunday when a lorry carrying them rolled down into a gorge at Peddavanka forest near Kuppam, 110 km from here.
The mishap occurred late on Saturday night as the driver lost control of the lorry while negotiating a curve, police said.
The rescue operation was underway but hampered by pitch dark conditions in the forest area, police said adding 12 injured people had been rushed to a hospital in Tamil Nadu.
More than 20 farm workers were being taken in the lorry to neighbouring Vaniyambadi in Tamil Nadu from Kuppam when the accident occurred.
Andhra Pradesh Chief Minister N Chandrababu Naidu expressed grief over the death of the workers.