Authorities are investigating how a farmer in the U.S. state of Oregon was devoured by his pigs, BBC News reported.

Terry Vance Garner, 70, went to feed his animals last week on his farm by the coast, but never returned. His dentures and pieces of his body were found by a family member in the pig enclosure, but the rest of his remains had been consumed.

The Coos County district attorney's office said that one of the animals had previously been aggressive with Garner. But investigators have not ruled out the possibility that the farmer could have suffered a medical emergency, such as a heart attack.

The animals are estimated by the authorities to weigh 700lb (320kg).