Two elderly Qatari women were tear gassed and robbed of millions on a busy Paris highway by two masked men.

In total, the value of the stolen items is estimated to be $5.6 million. The women's French driver, who regularly worked for them, reported the incident.

The women, both in their 60s, were being driven in a Bentley and had just left the French capital's Le Bourget airport when the robbers forced the vehicle to stop near a service station. 

A police source told The Guardian that the masked men stole "everything in the vehicle: jewels, clothes, luggage."

Robberies of wealthy foreigners are common along this particular stretch of highway heading north from Paris, according to Al Jazeera. Traffic jams near the 1.3 km Landy tunnel serve as an ideal opportunity for robbers to make their move.

This incident also follows a string of high-profile robberies of wealthy visitors to the French city. In October, U.S. reality TV star Kim Kardashian was bound and held at gun point in her hotel room when robbers made off with jewelry worth more than $10 million. 

Bollywood actress Mallika Sherawat and partner Cyrille Auxenfans were also the victims of an attempted robbery in their Paris home earlier this month. The robbers used tear gas but fled empty handed.

In 2014, a Saudi prince's convoy was the target of a heist similar to this week's robbery of the Qatari women.

High profile crimes in the wake of last year's terrorist attack in Paris are making it difficult for French tourism authorities to coax tourists back to Europe's leading cultural hub. Revenue from tourism is expected to drop by $1.6 billion in the city this year.