Thousands of Amazon workers have ended their days-long strike against the company, according to the Teamsters union. But tensions persist, with the union saying its efforts aren’t over.

With Christmas two days away, workers at four Amazon warehouses in Southern California are on strike Monday on claims the corporate giant refuses to recognize their union and negotiate fair contracts.

The Teamsters union is launching a strike against Amazon at numerous locations across the country, including in Maspeth, Queens.