European launch provider, Arianespace, was forced to indefinitely postpone the launch of one of its Ariane 5 rockets this week, due to protests at the French Guiana space center where the vehicle is meant to take off. Employees from two companies and a local hospital have been striking, partially over salary negotiations, and have prevented the Ariane 5 from getting to the launchpad for its launch.

The rocket is supposed to send two communications satellites into orbit — one for the Brazilian government and another for South Korea. Its launch was originally planned from Guiana Space Center for Tuesday, but Arianespace pushed the launch to Wednesday and then to today because of a “social movement.” Roadblocks made out of tires have been set up at the center by employees of Endel, the company that provides transportation for the space center, as well as employees of energy company EDF and employees of a medical center in Kourou, according to Le Parisien.

Endel’s management was able to reach an agreement with its employees on Wednesday, according to Ouest France. However, many of the roadblocks are still in place at Guiana Space Center and the blocks expanded last night, even causing schools in the area to close today. Some of the employees for the space center had to be flown into the site today to get to work.

Because of the growing protests, Arianespace decided to put the Ariane 5 launch on hold, without scheduling a definitive launch date. “The evolution of the situation does not permit the restart of operations for the Ariane 5 launch scheduled for today,” Arianespace said in a statement, but declined to comment further. Though, the company maintains the satellites “remain in a stand-by mode and are being maintained in fully safe conditions.”