That would require the police to believe that an offence is likely to have been committed. While I am more than ready to criticise the police for many, many things, I'm not sure they're likely to just take that at face value... (As you've specified first contact, etc., that seems likely - of course there could be situations where such a communication would be an offence, such as in the context of a restraining/exclusion order, etc., but not in this case).