Four people were yesterday charged with fraud at Work Programme provider A4e.
This comes on top of fraud nine arrests in September.
A4e chief executive Andrew Dutton said the company had "fully cooperated with police" in a statement on the company's website.
A4e is one of the main contractors on the Government's Work Programme, which is designed to help people off benefits and into work.
How can this go wrong? A former Work Programme participant wrote to David Blunkett, his local MP, to set out serious allegations about the company's internal workings.
By coincidence, the claimant later found temporary work in A4e's Sheffield head office in late 2012 and early 2013. He claims the company regularly claims credit for jobs they didn't find.
Following a rocky start, the Work Programme's results have been improving recently.
Figures released in June revealed only one in 20 sick and disabled people have been found lasting jobs.
However, its performance for other groups has improved: 31.9% of under-25s were found work for at least six months, almost hitting the minimum target of 33%.