French judicial officials said detectives from the Paris violent crimes squad interviewed another alleged Strauss-Kahn victim, journalist Tristane Banon, 32.
Banon, who in 2007 publicly accused the former IMF hear of trying to force himself on her "like a rutting chimpanzee," lodged a formal complaint last week against Strauss-Kahn.
After the police interviews, prosecutors in France will decide whether to charge the 62-year-old, who was formerly the opposition French Socialists' best hope to beat Nicolas Sarkozy in next year's presidential election.
Meanwhile, Strauss-Kahn, who faces seven criminal charges in New York for allegedly trying to rape a 32-year old hotel maid back in May, had been due to appear in a US court on July 18. On Monday however his court date was pushed back, at the request of both defense and prosecution attorneys.
The former IMF chief, who resigned his post with the International Monetary Fund in order to fight the charges against him, has denied the sexual assault and attempted rape of the maid in his luxury Manhattan hotel suite.
Strauss-Kahn's lawyer said Monday that his client filed a lawsuit for defamation against Banon late last week.
But the allegations threaten to overwhelm resurgent hopes that he could bounce back politically after being arrested in New York.
Those hopes had revived this month when the US case against Strauss-Kahn appeared to be in trouble amid doubts over the maid's credibility.
Banon, who is the god-daughter of Strauss-Kahn's second wife, Brigitte Guillemette, first made the allegations on television back in 2007.
In that broadcast, she accused Strauss-Kahn of trying to force himself on her, but said she was persuaded at the time that no-one would take her word against the powerful politician's if she sued.
The channel that aired those comments, Paris Premiere, said it will broadcast the show again on Wednesday. Strauss-Kahn's name was bleeped out but Banon confirmed in a separate interview she was referring to him.
Banon's lawyer David Koubbi said last week he had material evidence and witnesses to back her allegations.
In an interview published last week online by L'Express magazine, she repeated her account of the alleged attack, saying Strauss-Kahn had "his hands in my pants after he ripped off my jeans and bra."
She added: "Eight years ago when I talked about bringing a complaint, everyone had me believe that it would lead nowhere. In these matters it is one person's word against another."
When US media reported that prosecutors were poised to drop the charges, Banon said, "seeing Strauss-Kahn freed then afterwards dining in a fancy restaurant with friends, that makes me sick."
Banon's legal action prompted awkward questions for Socialists whom Banon says knew about her alleged ordeal at the time and did nothing.
She said former Socialist Party chief Francois Hollande, currently polling as the leading Socialist presidential candidate, was aware of the accusations, but he has insisted he had "no detailed knowledge" of the alleged incident.
Banon's mother, Socialist politician Anne Mansouret, confirmed she had advised her at the time not to make a formal complaint for fear of hurting her daughter's career in journalism.
Strauss-Kahn's allies, meanwhile, have branded Banon an opportunist.
"Clearly certain people are not happy about the return of Dominique Strauss-Kahn," Socialist MP Jean-Marie Le Guen told reporters last week.
Banon turned up for questioning by police on Monday morning and left in the early afternoon, said judicial officials who asked not to be named. They and people close to Banon gave no further details.