Diana

ALSO:

• Photographers' fate?
• Recent revelations
• Related stories and sites

PARIS (CNN) -- The investigation into Princess Diana's death has ended, 17 months after her death in a Paris car crash, French prosecutors said Friday. But the case is hardly over.

Because of procedural requirements, it will take investigating magistrates a few more months to decide formally who is to blame and whether a trial is needed to close the case.

The Paris prosecutor's office said in a statement that Judge Herve Stephan, who is in charge of the investigation, had notified all parties in the case that the inquiry was over and they had 20 days, as required by law, to request any further tests or questioning.

After that, Stephan will make his conclusions known to prosecutors, who will have three months to decide what action to take -- if any.

The news came just hours after Stephan again interviewed the photographers implicated in the case to sort out some outstanding issues.

Diana, her boyfriend Dodi Fayed and their driver, Henri Paul, were killed in an August 31, 1997, car crash in a Paris traffic tunnel. Paul was drunk at the time, and that is still believed to be the main cause of the crash, along with excessive speed.

Photographers' fate?

But the fate of nine photographers and a press motorcyclist who were tailing the Mercedes limousine that night has yet to be resolved.

They have been placed under formal investigation -- one step short of being formally charged -- for manslaughter and failing to render aid to accident victims.

Many observers believe the manslaughter charges will be dropped, but a few photographers are expected to be formally charged and tried on the second, lesser charge.

The Paris prosecutor's office made the announcement after a morning in which Stephan interviewed at least five photographers at the Palais de Justice, the main courthouse in Paris.

Recent revelations

Lawyers said the questioning focused on recent revelations that one photographer, Fabrice Chasserie, had phone contact three times on the day of the crash with the owner of Etoile Limousine -- the company that rented the Mercedes to the Ritz Hotel.

Such contact would imply that the photographer had advance knowledge of the route the Mercedes would take. The judge wanted to know if other photographers had that information as well.

Defense lawyer William Bourdon, who represents photographer Nikolas Arsov, said he would ask the judge to dismiss the case against his client.

Besides the photographers, the civil parties that have 20 days to make additional investigative requests include Mohamed Al Fayed, father of Dodi and owner of the Ritz; Diana's mother, Frances Shand-Kydd; the parents of Henri Paul; and bodyguard Trevor Rees-Jones, sole survivor of the crash.

The parties could also appeal any decisions Stephan makes on their requests.

After that phase is over, "the dossier will be transmitted to the prosecution, which will have a period of three months to make known its definitive desires on the next steps of this procedure," the statement said.

The Associated Press and Reuters contributed to this report.