Pippa Middleton, the sister-in-law of Prince William, could face arrest after an incident in Paris where one of her friends brandished a gun in public, according to reports.

British tabloid The Sun reported that Middleton was with three male friends in a car when one of them pulled out what seemed like a semi-automatic gun, waved it in the air and pointed it at a photographer who was following them.

"If the gun was real, brandishing it in a public space is punishable by up to seven years jail for all parties involved," a source told The Sun.

Authorities would need to gather evidence that point at her involvement, according to the report.

The pictures of the incident were published by the tabloid.

Tags: Pippa Middleton