(a) Whoever, by any fraud or false pretense, enters or attempts to enter—

(1) any real property belonging in whole or in part to, or leased by, the United States;

(2) any vessel or aircraft belonging in whole or in part to, or leased by, the United States;

(3) any secure or restricted area of any seaport, designated as secure in an approved security plan, as required under section 70103 of title 46, United States Code, and the rules and regulations promulgated under that section; or

(4) any secure area of any airport,

shall be punished as provided in subsection (b) of this section.

(b) The punishment for an offense under subsection (a) of this section is—

(1) a fine under this title or imprisonment for not more than 10 years, or both, if the offense is committed with the intent to commit a felony; or

(2) a fine under this title or imprisonment for not more than 6 months, or both, in any other case.

(c) As used in this section—

(1) the term "secure area" means an area access to which is restricted by the airport authority, captain of the seaport, or a public agency; and

(2) the term "airport" has the meaning given such term in section 47102 of title 49.