Amazon has fired two employees with ties to the grassroots union that led the first successful U.S. organizing effort in the retail giant’s history.

The company confirmed Tuesday it fired Michal, or ‘Mat,’ Cusick and Tristan Dutchin of the Amazon Labor Union in New York. It claims the cases are unrelated to each other and unrelated to any cause or group the two support.

Cusick says he was fired for COVID-related leave after receiving conflicting messages from the company about when the leave period ended. Amazon spokesperson Kelly Nantel says Cusick failed to show up for work after the leave ended in April.

Dutchin failed to meet productivity goals, Nantel said. Dutchin did not respond to a request for comment.