The recent escape of several research monkeys after the truck carrying them overturned on a Mississippi interstate is the latest glimpse into the secretive industry of animal research and the processes that allow key details of what happened to be kept from the public.

Three monkeys have remained on the loose since the crash on Tuesday in a rural area along Interstate 59, spilling wooden crates labeled “live monkeys” into the tall grass near the highway. Since then, searchers in masks, face shields and other protective equipment have scoured nearby fields and woods for the missing primates. Five of the 21 Rhesus macaques on board were killed during the search, according to the local sheriff, but it was unclear how that happened.

Key details remain shrouded in secrecy

Mississippi authori

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