Brecon and Radnorshire MP Chris Davies has been interviewed by police about an allegation of fraudulent expense claims.
The Conservative MP spoke voluntarily to the Metropolitan Police Service (MPS) earlier this week, after being referred by the Independent Parliamentary Standards Authority (IPSA) over a claim for pictures for his constituency office.
Mr Davies has previously said he made an "honest mistake" in the way he submitted the claim but said he did nothing wrong.
It is understood that he is accused of manually creating two invoices for £450 and £250 rather than submitting the full £700 claim.
He has previously said he repaid £450.