French investigators on Monday quizzed presidential hopeful Francois Fillon and his wife Penelope over allegations that Penelope received €500,000 ($535,000) for a fictitious job as a parliamentary aide, legal sources said.

The couple, who are the target of an embezzlement probe, were also questioned over payments Penelope received from a literary review owned by a billionaire friend of Francois Fillon.

After the scandal broke last week Fillon had apparently demanded an early opportunity to put his version of the story to investigators and on Monday he and his wife were questioned separately.

Marc Ladreit de Lacharrière the billionaire owner of the literary review La Reveu de Deux Mondes was also questioned by French police on Monday.

On Sunday Fillon hit back at the allegations telling a packed rally his critics should “leave my wife out” of the election.

“If someone wants to attack me they should attack me straight on, but leave my wife out of this political debate,” Fillon, a conservative who has been leading the presidential race so far, told thousands of cheering supporters, watched by his Welsh-born wife Penelope.

“I want to tell Penelope that I love her and that I will never forgive those who tried to throw us to the wolves,” he told the crowd, to chants of “Penelope, Penelope!”

Fillon has been scrambling to contain the damage to his campaign caused by allegations that his wife collected half a million euros ($534,000) as his parliamentary aide and then that of his successor over a period of eight years — for little to no work.

The claims first surfaced in the Canard Enchaine weekly, which mixes satire and investigative reporting.

Fillon has dismissed the allegations, which are dominating coverage of the campaign, as “mudslinging” and “misogynistic”.