15.— (1) A person who assaults or attempts to assault a bureau officer or a member of the staff of the Bureau or any member of the family F25 [ or the civil partner within the meaning of the Civil Partnership and Certain Rights and Obligations of Cohabitants Act 2010 ] of a bureau officer or of a member of the staff of the Bureau shall be guilty of an offence.

(2) A person guilty of an offence under this section shall be liable—

( a) on summary conviction, to a fine not exceeding F26 [ € 3,000 ], or to imprisonment for a term not exceeding 12 months, or to both, or

( b) on conviction on indictment, to a fine not exceeding £100,000, or to imprisonment for a term not exceeding 10 years, or to both.