We decided to sue and discovered that ICE had embarked on a nationwide program of warrantless immigration sweeps with names such as "Return to Sender" and "Community Shield" to invade private homes in search of undocumented immigrants.

CNN: Raided, for sleeping while Latino

Although the sums involved are very small in terms of its annual turnover, the Royal Mail says the proceeds are used to recoup part of the cost of its National Return Letter Centre based in Belfast, which aims to return undeliverable items to the sender wherever possible.

BBC: How much does Royal Mail make from undelivered parcels?

If you ask me, I think Elvis said it best about such messages: Return to sender, address unknown, no such number, no such zone.

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