It's hard to say how they got out without seeing what their cage look like. Their can use trunk to do a lot of things , I bet I know why they got out , the poor things mostly bored to tears and do get enough exercise .
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Blech. Circuses are horrible places for animals. Abuse is rampant, they don't get the care they need and deserve. I refuse to ever go see one again. I have vague memories of my parents taking me to one when I was little.
Being tied up or boxed up and not have enough exercise except to performed in the circus. Also might have been abused, too. I feel sorry for any animal that suffered whether in the circus or the zoo.
They're being kept in a trailer according to the news report on TV. The poor thing have no room to move around . I would not go any circus , animals do not belong in cages most of their life.