Starbucks workers in the Baltimore area have joined another national strike as negotiations with the company have not begun and employees say union stores remain understaffed.

After workers protested Friday morning, the North Charles Street location in Midtown-Belvedere neighborhood did not open and will not for the remainder of the weekend, according to employees.

At 8:45 a.m. on Saturday, the store was closed. The outside windows were covered with signs in support of Starbucks Workers United, the labor group organizing the effort.

One of them read, “On ULP Strike Fri-Sat-Sun. We open Monday.” The abbreviation stands for unfair labor practice.

“Starbucks did actually meet with some of the stores in our union district that have unionized. But shortly after we agreed to meet with them, their representative who we have been talking to said they’re on long-term hiatus and won’t be available for communication,” Violet Sovine, the store’s strike leader, told The Baltimore Banner on Friday.

“And our store was not part of those initial negotiations,” Sovine added. “We’re very tired of being jerked around on this and not being given a clear answer on when negotiations can begin.”

More than 1,000 baristas at 100 stores are planning to walk out, according to Starbucks Workers United. The strike will be the longest in the year-old unionization campaign.

The union says it expects the strike will shutter some stores entirely; at others, managers or other workers may keep the stores open.

Starbucks, which opposes the unionization effort, said Friday that the strike was having a limited impact on its stores and most remained open.

“We remain focused on working together and engaging meaningfully and directly with the union to make Starbucks a company that works for everyone, and we urge Workers United to uphold their promises to partners by moving the bargaining process forward,” the company said in a statement.

The process has been contentious. According to the National Labor Relations Board, Workers United has filed at least 446 unfair labor practice charges against Starbucks since late last year, including that the company fired labor organizers and refused to bargain. The company, meanwhile, has filed 47 charges against the union, among them allegations that it defied bargaining rules when it recorded sessions and posted the recordings online.

The Midtown-Belvedere store joined Starbucks Workers United about eight months ago, making it the first location to organize in Maryland.

Another store in White Marsh’s Nottingham Square Shopping Center unionized sometime after, and has also joined the strike, according to a map provided by the union.

“Basically, we’re having the same problems that we were having before, where Starbucks is still not making any effort to bargain with us,” said Ezra “Alex” Boyd, a shift manger at the North Charles Street location who has worked for Starbucks for more than eight years in multiple states.

Boyd alleged that the store’s district manager allotted money for all the area stores to have a Christmas party, yet very pointedly said their store “was not permitted to partake in it.”

The store’s district manager also expects the store to operate at its usual level of efficiency despite decreased staffing, Boyd and Sovine said.

“We’re already understaffed, and anytime we have a call out or some instance where we really should — in all logic — be closed, our district manager simply tells us that closing is not an option,” Boyd said.

Rebecca Heis, the union district’s representative leader, said the strikes will not hurt the global coffee chain financially.

She also said that the employees do not want to “destroy” the company, but rather “return it to the company that it once was where they respected their employees.”

“Starbucks thinks they can fire their way out of having to deal with the union. They have fired well over 100 of our lead organizers, and in this region alone we have 10 or 11 charges filed for,” Heis said. “And for whatever reason Starbucks claims to be this wonderful and progressive company, which at one time they were, but as they grew, the less value employees had.”

Baristas across the country are asking people to sign a solidarity pledge and are asking for financial support through their Solidarity Fund to support workers at Starbucks engaged in workplace activism and organizing.

Union workers began applying for support in November and have so far accepted nearly $150,000, according to the donation site.

“The solidarity fund is the main way that people outside this struggle can help support us and help get us through the tumultuous times,” Sovine said.

Additional reporting by Dylan Segelbaum.

The Associated Press contributed to this report.