(CBS News) -- Pippa Middleton could reportedly face criminal charges stemming from paparazzi photos taken of her in Paris over the weekend.
The 27-year-old sister of Kate, Duchess of Cambridge, was riding in the passenger seat of an Audi convertible on Sunday with three male friends when the driver pointed what appears to be a semi-automatic handgun at a photographer, according to Britain's The Sun.
A source told the tabloid, "If the evidence points to her involvement, she will be prosecuted. Anybody involved in the illegal use of a handgun in public is liable to arrest and interrogation."
"Certainly if you were in a car and knew somebody was using a gun to warn people off you'd be liable to arrest," the source added.
A person who witnessed the incident filed a formal complaint with Paris police, the Daily Mail reports. If the gun turns out to be real, those involved could face up to seven years in prison, the paper added. If the weapon is fake, the maximum sentence is two years.
According to the Daily Mail, Middleton was in the French capital to attend a birthday party for Paris fashion entrepreneur Arthur de Soultrait, who was reportedly riding in the backseat of the convertible on Sunday.
Buckingham Palace has not commented on the incident, according to reports.
Middleton became a paparazzi favorite after serving as maid of honor when her sister married Prince William almost one year ago. One newspaper editor has said he gets hundreds of photos of Pippa crossing his desk every day.
Jessica Derschowitz, CBS NEWS