Four Muslim men in France are suing the security firm they used to work after they were sacked for refusing to shave their beards.

The former security guards who worked at Orly Airport in Paris say they were discriminated against by Securitas in the wake of Paris terror attacks in November 2015.

The men were pressured to shave their beards, with the company telling them that many passengers were "on edge" after terrorists killed 89 people at an Eagles of Death concert in the Bataclan theatre and three suicide bombers blew themselves up a football stadium, an industrial tribunal heard on Thursday (7 September).

Less than a week after the attacks, the airport workers were suspended for refusing to shave their beards. Several months later, they received letters telling them that they had been fired.

"They'd had beards for years and then suddenly that becomes a problem," their lawyer, Eric Moutot, told French news website 20 Minutes, denouncing the "paranoia" that seized the company following the terror attacks.

Securitas has denied that it is guilty of discrimination and said that all its workers are required to adhere to the company's rules which state that facial hair must be kept short and well-groomed.

The tribunal will consider whether a beard can be considered a religious symbol.

In March, the European Court of Justice ruled that companies should be allowed to ban their staff from wearing religious symbols. After the Paris terror attacks, French authorities tightened security around airports and screened everyone working at the capital's two airports, Charles de Gaulle and Orly.

Almost 70 workers had their security passes revoked because of "cases of radicalisation." More than 85,000 workers, including baggage handlers, aircraft cleaners and sub-contractors have access to secure zones in the two airports, according to their chief executive officer Augustin de Romanet.

Place de la Republique
Parisians light candles and lay tributes on the monument at Place de la Republique following a series deadly terrorist attacks in Paris Christopher Furlong/ Getty Images