PHILADELPHIA (AP) — U.S. Sens. Pat Toomey and Bob Casey say the Navy has agreed to commission the USS Somerset in Philadelphia.

The Pennsylvania senators say the USS Somerset is the Navy’s newest amphibious transport dock ship and was christened the Somerset in remembrance of the western Pennsylvania county where hijacked United Airlines Flight 93 crashed during the Sept. 11, 2001 terrorist attacks.

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The USS New York and USS Arlington are so named to commemorate the other sites attacked that day, the World Trade Center towers and the Pentagon.

The USS Somerset was christened, or named, in July.

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A ship is commissioned when it is formally put into active service.

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