Transportation Security Administration agents are used to finding firearms and other weapons in checked luggage.

However, last week TSA officials acknowledge discovering a weapon that they probably will add to “items we don’t see every day” category” —  an unloaded cannon barrel in a passenger’s checked luggage at the Kahului Airport.

The cannon barrel was found in the checked bag of a United Airlines passenger traveling to  San Francisco on Oct. 20 at around 9 p.m.

The airline made separate arrangements to transport the item for the passenger and the passenger was cleared to fly, the TSA reported.

TSA agents have found cannon balls in the past, but never a cannon.