Earlier this week, Sanders faced criticism about his "Medicare for All" policy from the influential Nevada Culinary Workers Union.
The culinary union claimed that his policy would put an end to the private healthcare plans that its members fought hard to win from their employers.
Sanders supporters began criticizing the union's claims online, prompting the group put out a statement on Wednesday, calling out the candidate's backers for "viciously" attacking the union, according to a previous report from The Hill.