Yes you can be arrested, and yes it is serious.
Fraud by false representation
(1) A person is in breach of this section if he�
(a) dishonestly makes a false representation, and
(b) intends, by making the representation�
(i) to make a gain for himself or another, or
(ii) to cause loss to another or to expose another to a risk of loss.
(2) A representation is false if�
(a) it is untrue or misleading, and
(b) the person making it knows that it is, or might be, untrue or misleading.
(3) �Representation� means any representation as to fact or law, including a representation as to the state of mind of�
(a) the person making the representation, or
(b) any other person.
(4) A representation may be express or implied.
(5) For the purposes of this section a representation may be regarded as made if it (or anything implying it) is submitted in any form to any system or device designed to receive, convey or respond to communications (with or without human intervention).