Several MPs are said to have claimed too much for their council tax
More than 50 MPs have claimed expenses for council tax they have not paid, the Daily Telegraph says.
They are said to have claimed more than the rates of tax published by councils.
The new expense allegations came after police launched a criminal inquiry into an alleged misuse of expenses by a small number of MPs and peers.
Police say its economic and specialist crime command will investigate, following a public outcry about the way some MPs used their allowances.
The BBC understands that former Labour minister Elliot Morley is one of the MPs under scrutiny by police, as is another Labour MP, David Chaytor.
Both allegedly claimed interest on mortgages they had already paid off.
A Labour peer, Baroness Uddin, may also face questions about her use of a flat in Maidstone.
In new revelations by the Telegraph - which has obtained expense claims made by all MPs - it is alleged that politicians claimed for council tax on second homes in excess of town halls' published rates by house band.
The paper also said 18 of the 50 politicians accused over their council tax claims had already made re-payments to the Commons Fees Office.
The Telegraph says Labour MP Eric Illsley was accused of over-claiming by more than £6,000 between 2004 and 2008.
Mr Illsley said the claims were submitted during a period when receipts were not required.
Until recently, MPs only needed to provide receipts for claims higher than £250 a month.
Many MPs claimed a notional amount which wasn't related to the actual bill, he said.
"This is why the claims do not match the council tax bills. It is embarrassing. I'm sorry it has happened.
"I have never made any secret of my claims and I will pay back the money."
Former minister Beverley Hughes was said to have profited by up to £2,000.
She told the paper she was checking her records, but did not believe the amount was as much as that.
Former home secretary David Blunkett told the Telegraph he may have over-claimed by £178.
The expenses row has enveloped all the major parties
His spokesman said: "David's pretty mortified to have been caught up in this at all, especially as his is the lowest amount of any of them listed in the Telegraph this morning.
"We'll be checking the exact amount on Monday with the Fees Office, and we're presuming what's an 85p-a-week shortfall is down to rounding up.
"If there is a shortfall and there is money to be repaid then David will obviously repay it straight away."
Government whip Mark Tami has allegedly profited by about £1,500.
Mr Tami said: "I am going to look into whether I have over-claimed and if I have then clearly I will pay back any over-claim."
Tory MPs David Willetts and Jeremy Hunt admitted to having over-claimed for council tax by about £500 each, the Telegraph said.
Mr Willetts said it was possible that he had "inadvertently" claimed for an 11th month while his council tax bills were divided into 10 payments.
"If I have inadvertently made incorrect claims I will of course pay any money back," he said.
In May, the Labour MP for Stafford, David Kidney, paid back about £2,500 that the Commons authorities mistakenly paid him.
"It's not factually true that I made inflated claims," he said.
"The Fees Office made a series of mistakes leading to me being overpaid and that's why I've had to pay money back. The Fees Office letter is on my website".
In a separate development announced on Friday, Scotland Yard confirmed it would investigate claims made by some MPs and peers.