The policeman followed the thieves until they actually picked up the jewellery, where he caught them red-handed.

警察尾随着小偷，直至他们行窃珠宝时当场将他们逮捕。

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When they had picked up the food, he caught them and made them return through a different channel, which also led to the nest.

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He caught them on a technicality though.

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Mr. Crumpton refused to say where he and his teammate caught them or how, fearing a competitor would move in on their territory.

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