Police initially said the two victims were critical, but Cazeneuve said just the policewoman was fighting for her life.
The incident comes on a day of mourning in France after Islamist gunmen stormed the office of satirical magazine Charlie Hebdo on Jan. 7, killing eight journalists, two police and two others.
The men are still thought to be on the run, and there has so far been no claim of responsibility for the massacre that has deeply shocked France.
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