Six former employees of French video game developer Eugen Systems allege their recent firings were retaliation for a strike that occurred last year, but the studio is disputing that claim. In a statement to Variety, it said it had to take action against the workers because they “used a professional tool for an inappropriate purpose.”

“What we have discovered, in the presence of a bailiff (in order to guarantee compliance with the procedure and in absence of individual character or privacy), is against our values and our corporate culture,” Eugen said. “As any employer, we have an obligation to prevent situations that could be prejudicial to our employees’ health and safety, therefore we have been forced to make a decision accordingly.”

Eugen Systems was founded in 2000 and is based in Paris. It mainly creates real-time strategy games for PC and Mac. Some of its past projects include “Steel Division: Normandy 44,” “Act of Aggression,” and the “Wargame” series.

Many of its employees went on strike in February 2018 over a wage dispute. They claimed Eugen was paying them less than the mandated minimums set in their contracts. The strike lasted about a month and a half but was ultimately called off after negotiations stalled. About 15 workers and the independent union Le Syndicat des Travailleurs et Travailleuses du Jeu Vidéo (STJV) are now bringing a case before a French labor tribunal in March.

Although the STJV said it believed the firings were an “act of retaliation and a preemptive move by management,” Eugen told Variety its decision was not linked to the strike. One of the six people involved never took part in it, the studio added.

“We have fully respected our employees’ right to strike, and our team still comprises those who were on strike, including one employee who has since been promoted to a managerial position,” it said. “Our team currently counts 26 employees and will continue growing in the coming weeks.”

Variety contacted the studio for more information, but it did not immediately respond.