OAKLAND (AP) — About 3,000 Oakland city employees went on strike Tuesday to protest what they said are unfair labor practices.

The largest union on strike is Service Employees International Union Local 1021, which represents more than 2,000 public works employees, parking enforcement officers, Head Start instructors, and early education teachers.

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International Federation of Professional and Technical Engineers Local 21, which represents about 1,000 professional and technical employees, including engineers, building inspectors and planners, is engaging in a sympathy strike with SEIU Local 1021.

In addition, about 20 city employees who belong to Local 1245 of the International Brotherhood of Electrical Workers are respecting Local 1021’s picket lines.

SEIU Local 1021 spokesman Chris Flink said the union believes its strike is legal because it’s an unfair labor practice strike, which he said it lawful and protected activity.

Flink said the strike will continue “until the city comes back to the bargaining table.”

He said no further negotiations are scheduled as of Tuesday afternoon, so it appears likely that the strike will continue on Wednesday.

The city rejected the union workers’ offer to have former San Francisco Mayor Willie Brown mediate the talks.

Many city workers were walking picket lines outside closed offices as thousands of residents were forced to go without essential services.

City workers told KPIX 5 they just want to be paid enough to survive in the Bay Area.

“We don’t want to be on strike. We gave the city every opportunity to avoid this strike,” said Oakland city employee David Velez.

The major sticking point: The city wants to tie the second year of a two-year contract to revenue growth, while the union wants a guaranteed four-percent raise.

Oakland Mayor Libby Schaaf apologized to about 400 families who didn’t have childcare Tuesday because Head Start program workers were also on strike.

Schaaf said Oakland would have to cut city services to meet the union demands.

“I recognize their frustration, but I cannot spend money I don’t have. I can’t. It’s not responsible to anyone,” said Schaaf. “So I’m not casting blame. I’m recognizing that both sides have legitimate reasons to be frustrated. But that’s why we have to put that frustration aside and get back to the table.”

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“I think she could look a little harder,” countered Neighborhood Services Coordinator Renee Sykes. “There’s some money somewhere and she doesn’t look at us as a priority. We are a priority.”

Michael Pandolofo said he just wants a full-time job after 18 years of working for the city.

The unions are calling the use of part-time workers like Pandolofo an “unfair labor practice” which needs to stop.

“It’s unconscionable to me,” Pandolofo. “So you’re saying I’m good enough to be part time, but I’m not good enough to be permanent.”

As long as this strike continues, facilities like senior centers, public libraries and recreations centers will remain shut down. There are also no workers for street sweeping, maintenance work or parking enforcement.

Schaaf says the strike is unlawful because the two sides have not reached an impasse.

Police and fire services have not been affected.

Flink said employees were conducting an informational picket at the corner of Broadway and 14th Street that started at 5 p.m. Tuesday, near the site where Schaaf will host a fundraising event for her re-election campaign.

Union officials said it costs $1,600 per person to attend the fundraising event.

Members of Service Employees International Union Local 1021 have worked without a contract since June 30. The union says the city underpays and relies too much on temporary help.

Members of an engineers union say they will honor the picket lines.

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