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Kate Middleton's sister Pippa could be in hot water after a male companion she was traveling with allegedly brandished a gun and pointed it at a paparazzo in Paris.

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London's The Sun reports that on Sunday the sister-in-law of England's presumptive future king was in the passenger seat of an Audi convertible when her male companion driver allegedly jokingly aimed a semi-automatic gun at a pap who was tailing them. The moment was caught on film by the French photographer/target, who may file a formal police complaint. Two other men were also in the car with Pippa at the time.

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The Sun says that Pippa is "facing a grilling by outraged cops" over the incident as the country remains especially sensitive following a series of gun massacres across France. A source tells the paper that charges could result in prison sentences of up to seven years for all four people in the car, or a two-year sentence if the gun turns out to be a fake.

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Pippa was reportedly in Paris to attend a costume birthday party as a guest of fashion label owner Arthur de Soultrait, who was one of the passengers in the car during the gun-brandishing incident.