Workers with Service Employees International Union Local 721, which represents more than 7,000 city employees, walked off the job Tuesday, interrupting or halting an array of government operations in a boisterous demand for respect.

The 24-hour strike brought picket lines to City Hall, Grifith Park, Van Nuys Airport, Los Angeles International Airport and municipal facilities in Hollywood, Lincoln Heights, San Pedro, the San Fernando Valley and elsewhere. City workers, marching in single file and clutching signs, spoke unhappily about increased workloads, rising housing costs, long commutes and what they described as unfair labor practices by city negotiators.

At the same time, the demonstrations lacked some of the heat and anger that surfaced in recent months during prolonged strikes by other Southern California unions — hospitality workers and Hollywood’s writers and actors. In the city’s back-and-forth, both sides promised more talks very soon, saying they want productive negotiations.

At one point, SEIU Local 721 President and Executive Director David Green even offered praise for Mayor Karen Bass, who heads the city’s five-member bargaining committee. Appearing at a noisy rally outside City Hall, he called on an estimated 2,000 workers to applaud the mayor, who oversees the negotiators he has repeatedly derided as “out of touch.”

“This strike is not a strike against our Mayor Karen Bass. She’s always been there for working people,” he told the crowd. “So I think let’s give a round of applause for the mayor right now.”

Green said he spoke with Bass the day before the strike, and since then fielded phone calls from at least four council members, who will ultimately vote on any salary agreement with the SEIU. Those council members, he said, “want to come back to the table.”

Councilmember Hugo Soto-Martinez, a former labor organizer, separately described the strike as “an opportunity to listen to the workers who perform the most essential functions in our city.”

“These workers deserve to be heard and they deserve a fair contract with livable wages and healthy working conditions,” he said in a statement.

Bass has repeatedly pushed back on the idea that city negotiators had engaged in unfair labor practices. She and the other four members of the city’s Executive Employee Relations Committee, which gives bargaining instruction to city negotiators, are scheduled to meet Wednesday to discussion negotiations with the SEIU.

“The city will always be available to make progress with SEIU 721 and we will continue bargaining in good faith,” she said.

Even amid Tuesday’s show of union strength, the city continued to deliver an array of services.

The Los Angeles Zoo, which has SEIU members in its workforce, nevertheless welcomed visitors. Dozens of branch libraries opened their doors. The city’s 311 system fielded service requests. All six animal shelters, which city leaders had assumed would be closed earlier in the week, were up and running, Bass said.

SEIU Local 721, which represents gardeners, mechanics, custodians, trash truck drivers and many other city workers, began its strike at 12:01 a.m., describing it as a protest against unfair labor practices by management and a rebuttal to the city’s failure to negotiate in good faith.

Outside LAX, dozens of mechanics and custodians began marching before dawn. By 7:30 a.m., the crowd had grown to about 100. Several voiced frustration over the large number of vacant positions that plague city agencies, forcing workers to take huge amounts of overtime.

DeVonte Butler, a 33-year-old maintenance and construction worker at the airport, said he and his colleagues are “working around the clock to catch up.” Although he has been earning extra money working overtime, Butler said the high cost of housing and childcare had left him living paycheck to paycheck.

Custodian Hilda Sotelo, 49, voiced similar concerns, saying the sprawling terminals of LAX once had double the number of cleaning staff. Last year, 66 million passengers made their way through the LAX, the most since the pandemic.

Sotelo said she and her colleagues are stressed out while scrubbing bathroom after bathroom. When they go on break, she said, passengers ask them for directions or other information.

“We are doing the work of three people,” she said.

Despite the presence of scores of striking workers, most of the airport’s operations continued without interruption. With fewer custodians on duty, some bathrooms were closed. Flights that typically require shuttles were rerouted to other gates.

Dae Levine, a spokesperson with Los Angeles World Airports, said the agency was working to ensure that operations were “as close to normal as possible.”

Tuesday’s walkout also had a significant effect on the city’s recreation sites, triggering the closure of dozens of swimming pools. In Boyle Heights, parents arrived at the gate of Roosevelt Pool only to find it had been padlocked.

“Nobody even told us they were canceled,” said Crystal Bedoy, ushering her sons back into the family’s white sport utility vehicle. “Usually my sister gets a phone call, but none of the parents have heard from anyone.”

The disruptions also stretched to the city’s southernmost edge.

At the Port of Los Angeles, about 300 Harbor Department employees are represented by SEIU, including deckhands and pilot service boat operators, who play a pivotal role in ensuring a cargo vessel’s arrival. With those workers on strike, four container ships had their arrival delayed by one day, according to a department official.

Two other containers ships postponed their departure.

“The Port looks forward to the return of a full work force on Wednesday,” said Phillip Sanfield, a spokesperson for the agency.

Across the city, residential trash pickup was canceled, delaying refuse removal schedules by one day for the remainder of the week. Homeless encampment cleanups scheduled for Tuesday by the Bureau of Sanitation were rescheduled to Saturday.

Sanitation worker Richard Joyal, who held a picket sign outside City Hall, said he showed up to Tuesday’s rally in the hopes that it would spur city officials to return to the bargaining table. He expressed some sympathy for residents who would not receive refuse collection Tuesday.

“We hope the residents will understand and back us,” said the West Covina resident, who works on a city team that collects mattresses and other bulky items left on the sidewalk.

SEIU Local 721 is currently operating under a one-year contract that has provided its members with a 3% raise and a one-time bonus equal to 5% of a worker’s annual salary. That bonus was paid out in a single lump sum last month.

The union has not yet submitted a proposal for its next contract. Instead, labor leaders have spent part of this year in negotiations over more than 400 side proposals, which deal with such issues as bilingual pay and compensation to help pay for boots or other safety equipment.

SEIU Local 721 filed an unfair labor practices claim several weeks ago, after city negotiators attempted to combine the talks over those side issues with bargaining over the union’s next contract. City Administrative Officer Matt Szabo, the city’s lead negotiator, denied that his office engaged in unfair labor practices, saying the two sides have already reached agreement on dozens of side issues.

City Council President Paul Krekorian said the city’s negotiating team had been engaged in “serious negotiations” with the Coalition of L.A. City Unions — a group that includes SEIU — since January, reaching 76 tentative agreements.

“Although today’s work stoppage is regrettable, the city will continue to negotiate in good faith with the coalition, and I have every confidence that we will achieve a positive outcome,” he said in a statement.

The union’s contract includes language barring its members from going on strike or staging “other concerted action resulting in the withholding of service.” However, state labor law allows the union to go on strike to protest unfair labor practices, according to SEIU officials.

Green, the SEIU president, portrayed Tuesday’s 24-hour strike as a success, saying it has given the union “a lot of momentum” as it heads back into negotiations. The walkout, he said, showed that the city’s workers “are really a force to be reckoned with.”

“The days of disrespecting city workers is over,” he said. “And you’re seeing it with solidarity summer.”