5. (1) A person who, for the purpose of obtaining sexual gratification from the presence of a child or corrupting or depraving a child, intentionally engages in sexual activity whether or not with another person—

(a) when the child is present or in a place from which the person can be observed by the child, and

(b) knowing or believing that the child is aware, or intending that the child should be aware, that the person is engaging in sexual activity,

shall be guilty of an offence and shall be liable on conviction on indictment to imprisonment for a term not exceeding 10 years.

(2) In this section “child” means a person under the age of 17 years.