More politicians could come under police investigation over fraudulent expenses, the head of Scotland Yard said today.
Sir Paul Stephenson said the number of suspects could "change significantly at any time" as inquiries flush out more suspicious claims.
The senior officer declined to reveal exactly how many parliamentarians are under scrutiny or when files might be passed to prosecutors.
But Sir Paul admitted more MPs and peers could be referred to police as a result of the massive shake up taking place.
Speaking at New Scotland Yard today, he said his officers are focussing on a "handful" of individuals.
Asked how many inquiries are under way, Sir Paul said: "It is a handful, more single figures than double figures.
"I have got to be really careful because it does not seem to me that we are at the end of this trail and suddenly we could have more people being referred.
"I would stick at around a handful but it could change significantly at any time. It does not seem to me that the story is going away."
Asked when files of evidence might be passed to prosecutors, Sir Paul added: "We will do it as soon as possible.
"We will do it properly and we will make sure it is thorough and when we do put something across we will make sure it is something that the CPS can make a decision on."
Sir Paul said he has a team of "fantastic detectives" who had involved prosecutors earlier after learning lessons from previous sensitive investigations.
Scotland Yard launched several inquiries into allegations politicians abused their expenses and allowances in June.
As a torrent of evidence of dubious claims flooded out of Westminster, police focussed on individuals who claimed so-called "phantom mortgages".
Among them is former Labour minister Elliot Morley who claimed £16,000 interest payments on a property where the loan was already paid off.
It emerged he claimed around £800 a month mortgage interest on his Scunthorpe home for about 18 months after the loan was repaid.
Other politicians believed to be under police investigation include Labour MP David Chaytor and Labour peer Baroness Uddin.
Bury North MP Mr Chaytor claimed £13,000 for a mortgage he had paid off. He has since confessed to an "unforgivable error".
Baroness Uddin faced claims she said an empty flat in Maidstone, Kent, was her main home so she could receive expenses for peers based outside the capital.
Detectives have yet to make any arrests but have been liaising closely with the Crown Prosecution Service and parliamentary Fees Office.
Her Majesty's Chief Inspector of Constabulary Denis O'Connor published a report into the bungled Damian Green leak inquiry last week.
He said police must be able to vigorously pursue political investigations without "fear of favour".