Lab monkeys on the loose in Mississippi don't have herpes, university says. But are they dangerous?

A portrait photograph of a rhesus macaque looking at the camera. .

Lab monkeys initially thought to be carrying a range of diseases have escaped from a truck in Mississippi following a crash — prompting law enforcement officers to kill a number of the animals. However, it's still unclear just how dangerous they are.

The truck, which was carrying rhesus macaques (Macaca mulatta) from Tulane University, overturned in Jasper County on Tuesday (Oct. 28), with several monkeys breaking loose — although the exact numbers have yet to be reported.