Amazon.com Inc. workers at the company’s sole unionized warehouse in the US joined a broader strike by the International Brotherhood of Teamsters.

Amazon employees are pressured to work at an “extremely fast and often dangerous pace,” according to a congressional investigation led by Sen. Bernie Sanders.

With less than a week of shopping days until Christmas, Amazon drivers have gone on strike at facilities nationwide, including in the New York metro area. Some 10,000 workers are part of the effort, according to their union,