Liberal Sen. Mac Harb is denying a 麻豆影视 report that he has to repay a significant amount of money for improperly claiming living expenses, but insiders say an audit will show he owes tens of thousands of dollars.

The audit is expected Thursday. Sources say he will have to pay up to $50,000 for a year and a half of housing and other expenses.

And because independent auditors have been instructed to scrutinize Harb鈥檚 expenses over the past seven years, sources say he could end up paying back more than $100,000.

Harb refused to answer questions from 麻豆影视 Tuesday, but told other media that he鈥檚 sure the auditors鈥 report will vindicate him.

Harb is among the senators whose housing and meal expenses were audited by the accounting firm Deloitte after concerns were raised about their living allowance claims.

Harb has told the Senate that his primary home is a bungalow in the village of Westmeath, located more than 100 kilometres northwest of Ottawa. But neighbours told CTV earlier this year that no one seems to live in the house year-round.

Senators can claim an annual housing allowance of up to $22,000 if their primary residence is more than 100 kilometres from Ottawa.

Independent Sen. Patrick Brazeau was also audited for claiming his father鈥檚 home in Maniwaki, Que. as his primary residence, even though he lived in a house in Gatineau, a short drive from Parliament Hill.

麻豆影视 reported Monday night that Brazeau will have to repay about $30,000.

CTV also reported that Conservative Sen. Pamela Wallin鈥檚 travel expenses will be examined from the day she was appointed to the Red Chamber in 2009. Sources said the auditors were alarmed by what they saw when they initially looked at about a year鈥檚 worth of her air travel expense claims. 

Special Senate caucuses will be held on Thursday, when senators will debate whether to refer the forensic audits to the RCMP.

Some want the Mounties called in.

鈥淭he RCMP and the justice department will obviously intervene. You can鈥檛 have something that is found to be fraudulent not referred,鈥 said Liberal Sen. George Baker.

Conservative Sen. Mike Duffy, who was also audited, has already repaid more than $90,000 for claiming his P.E.I. cottage as his primary residence, even though he has been a long-time Ottawa resident.

Sources say the Senate will lay out more stringent spending rules after the complete audit is tabled. 

With a report from CTV鈥檚 Ottawa Bureau Chief Robert Fife