Pippa Middleton caught up in Paris gun incident

Pippa Middleton, sister of Catherine, Duchess of Cambridge, watches Jo-Wilfried Tsonga of France play against Roger Federer of Switzerland during the singles final on day eight of the ATP World Tour Finals tennis tournament in London on November 27, 2011. Roger Federer won a record sixth ATP World Tour Finals title with a 6-3, 6-7 (6/8), 6-3 victory over France's Jo-Wilfried Tsonga on Sunday. With this win he moved ahead of Pete Sampras and Ivan Lendl on the list of Tour Finals champions in the 100th final of his majestic career. The 30-year-old, who retains the title he won 12 months ago, has now won 70 trophies in his career and has also equalled Lendl's record of 39 match wins in the end-of-season event.
GLYN KIRK/AFP/Getty Images
Pippa Middleton watches the ATP World Tour Finals tennis tournament in London on Nov. 27, 2011.

(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.

Pictures: Pippa Middleton

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.