French ex-President Jacques Chirac says he will fight for "truth and honour", after being placed under investigation for misuse of funds while Paris mayor.
Mr Chirac has always denied wrongdoing
Mr Chirac was questioned for more than three hours on Wednesday over the alleged embezzlement.
The case relates to a scheme whereby rightist sympathisers were allegedly given jobs by Paris city hall.
Last summer, Mr Chirac was questioned by another judge over allegations in the same case.
He lost immunity from investigation after he left the presidency in May.
He has consistently denied any wrongdoing while he was mayor of the capital between 1977 and 1995.
"I am going to fight at the same time for the truth and my honour," he said on the TF1 television channel.
"There has never been any personal enrichment and nobody can say otherwise, things are very clear," he added.
Party funding scandals
The fact that Mr Chirac has been placed under formal investigation means that judges believe there is enough evidence against him to proceed with a more exhaustive investigation, which may or may not culminate in a trial.
It could be the first time in modern French history that a former president faces criminal charges.
Mr Chirac's lawyer said an interview conducted by a magistrate with his client on Wednesday morning had been conducted in "the best possible atmosphere", AFP news agency reported.
"I simply think that he is not necessarily unhappy with the fact that for the first time he had an opportunity to explain himself on this issue," he said.
This investigation relates to allegations that during Mr Chirac's time as mayor of Paris, up to 40 people were paid salaries by the city authority despite having had no connection to it.
They are alleged to have been supporters of Mr Chirac's own conservative RPR political grouping.
Scores of people have been disgraced by the courts in party funding trials, including several of Mr Chirac's own close associates.