OAKLAND — Thousands of city workers in Oakland went on strike Tuesday, shutting down street cleaning, library and other public services after union leaders and city officials couldn't agree on a new labor contract.

Police and fire services are not affected but city officers were closed and parking regulations will not be enforced.

Like the rest of the San Francisco Bay Area, the city of 400,000 people is seeing housing costs skyrocket, and employees say their salaries are not enough to keep up with rising costs.

The city and union have agreed to a 4 percent salary increase in the first year but are stuck on increases for the second year. The city has offered a 2 percent increase if certain revenue conditions are met, but the union wants the city to commit to another 4 percent increase.

Talks broke down Monday after the city refused a union proposal to bring in an informal mediator.

About 3,000 workers in senior centers, libraries, City Hall and other city-run departments began their strike at 7 a.m.

Members of Service Employees International Union Local 1021 have worked without a contract since June 30. Members of an engineers union also joined the walkout.

Mayor Libby Schaaf said in a release Monday the city would file a labor complaint because the strike is unlawful. She said the two sides have not reached an impasse.

Schaaf said she wants a fair contract that is fiscally prudent. While she deeply values city workers, she said, "we cannot spend more than we can afford."