Fresno, Calif. (Fox26) — ‘Tis the season to mail packages right? Workers at a Fresno post office got quite the surprise when a man tried to ship something that isn’t exactly ideal for “priority mail” – puppies!

United States Postal Service says you can’t mail puppies kittens or certain warm blooded animals. It’s a felony to do so.

The United States Postal Service says a man walked in with boxes marked ‘birds’ and when a worker asked the man what was in the boxes and he said birds.

Workers say there were some birds inside the boxes, but there were also two puppies inside a different box with no food or water.

You can also mail certain cold blooded animals like baby alligators, frogs and chameleons. USPS says they must not require any food, water or attention during travel. There are other requirements animals must meet in order to be shipped.

Read more: Fresno man tries to mail puppies to North Carolina | KBAK