TREDYFFRIN TOWNSHIP, Pa. (CBS) — Police in Chester County say they’ve arrested someone for stealing mail from mailboxes in Tredyffrin Township. The county tells CBS3 the suspect took a number of checks as well as gift cards and credit cards.

Police believe they were stolen between Nov. 1 and Dec. 12. They’re urging everyone to double-check their accounts.

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Meanwhile, post office officials in Philadelphia say they’ve started replacing locks on hundreds of collection boxes because of a recent wave of thefts.

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Someone has been taking checks and trying to get mail carriers’ keys.

The post office says they aren’t sure how long it will take to replace the locks, but they’re working as quickly as possible.

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They have about 1,500 boxes to get to.