Underpaid 7-Eleven workers have been physically intimidated, and in one case beaten, to discourage them from seeking repayment, a senate inquiry has heard.

Key points: 7-Eleven set up an independent panel to assess the claims of around 20,000 past and present workers over pay and conditions

7-Eleven set up an independent panel to assess the claims of around 20,000 past and present workers over pay and conditions Senate inquiry told workers were physically intimidated to discourage them from seeking repayment

Senate inquiry told workers were physically intimidated to discourage them from seeking repayment Already around $2.8 million has been paid to 117 workers, an average of about $24,000 per claimant

Last year, ABC's Four Corners program and Fairfax revealed workers at the convenience stores were systematically paid about half the minimum wage. Many of those affected were foreign workers.

The convenience store chain set up an independent panel to assess the claims of about 20,000 past and present workers from the convenience store's franchises.

The head of the panel, Professor Allan Fels, has told a senate committee several employees faced threats from franchisees.

"You'll lose your job, you'll be reported to immigration and your chances of being deported are very high and, in any case, any money you get we will demand it back from you," Professor Fels said.

"And there have been some threats of physical intimidation."

Another member of the panel, Siobhan Hennessy from Deloitte, told the committee she was aware of one example where an employee alleged he was intimidated with physical violence.

"A claimant being beaten ... it's unbelievable," Ms Hennessy said.

She said the claimant went to the police but was told it was a matter they should sort out directly with their employer.

The inquiry has heard about $2.8 million has been paid so far to 117 workers, an average of about $24,000 per claimant.

Professor Fels told the committee he was concerned only 2,100 employees had so far indicated they might lodge a claim.

"At present, 60 per cent of stores have a claim against them and there are probably more that should have a claim against them," Professor Fels said.

He said the intention of 7-Eleven head office to recoup some of the cost of the repayments from their franchisees contributed to the problem.

He said that put an extra obligation on the head office to make sure claimants were not intimidated from coming forward.

7-Eleven chairman Michael Smith said the company was working with the independent panel.

"7-Eleven is working cooperatively with Professor Fels in a number of ways, including the provision of documents, enabling access to stores and promoting the existence of the panel and its work to encourage potential claimants to come forward," Mr Smith said.

Professor Fels told the committee initially 7-Eleven head office was in denial about the extent of underpayment and exploitation, and while they had improved, he said there was a considerable way to go.

He also told the committee his panel had concerns about some 7-Eleven regional managers being involved in the underpayment rackets.