Updated

A U.S. importer of research monkeys was set to stand trial Monday on cruelty charges after 15 primates died during an international flight.

Robert Matson Conyers, a Florida animal broker, faces 10 counts involving a 2008 plane trip from Guyana. Officials say Conyers was shipping 25 monkeys to a buyer in Bangkok, but the shipment was refused transit in China and returned to Los Angeles.

The monkeys wound up on a circuitous trip across thousands of miles with stops in Bangkok, Miami and twice in Los Angeles. They suffered from neglect, starvation and hypothermia in transit, authorities say, and 15 eventually died.

Fourteen marmosets, five white-fronted capuchins and six squirrel monkeys were turned back in China over paperwork issues such as irregularities in the shipping documents.

Officials in Los Angeles found 14 of the 25 monkeys packed into crates were dead.

Los Angeles Zoo veterinarians administered emergency care to the survivors, but a capuchin had to be euthanized. The rest are recovering at the San Diego Zoo's Wild Animal Park.

The advocacy group Stop Animal Cruelty Now said the monkeys were dehydrated and resorted to cannibalism during their long journey.

Once the story of the monkeys' flight was reported, monkey imports to Los Angeles were halted.

The advocacy group said the United States is the largest importer of monkeys coming from the Philippines, Indonesia, Guyana and Kenya. Most are destined for laboratory experiments.

Conyers could face up to six months in jail and a $20,000 fine if convicted.