(1)A direction under section 21—
(a)may be given orally;
(b)may be given to any person individually or to two or more persons together; and
(c)may be withdrawn or varied by the constable who gave it.
(2)A person who, without reasonable excuse, knowingly contravenes a direction given to the person under section 21 shall be guilty of an offence and liable on summary conviction to—
(a)a fine not exceeding level 4 on the standard scale; or
(b)imprisonment for a term not exceeding 3 months,
or to both.
(3)Where a constable reasonably suspects that a person has committed or is committing an offence under subsection (2), the constable may arrest the person without warrant.
(4)Subsection (3) is without prejudice to any power of arrest conferred by law apart from that subsection.