A neighborhood activist group filed suit Thursday against the city of Los Angeles seeking to block implementation of a zoning code overhaul.

L.A. Neighbors United filed suit in Los Angeles Superior Court, alleging that the city violated provisions of the California Environmental Quality Act by not conducting a thorough environmental review of the zoning code changes.

The lawsuit seeks a judicial order forcing the city to set aside the code changes until a thorough environmental review is completed.

The City Council last month approved the first set of proposed changes, which center on zoning regulations for infill development. They clarify vague or outdated language in the current zoning code and attempt to consolidate requirements for development projects.

This past summer, Cary Brazeman and L.A. Neighbors United took out ads in local papers attacking the proposed changes, saying they would strip the ability of residents near development projects to object and would ultimately lead to projects with higher densities, bigger buildings and more traffic.

City planning director Michael LoGrande did not offer a direct response to the filing of the lawsuit. Instead, he referred to a document the Planning Department issued this week titled “Myths and Facts About the Planning Department’s Recent Initiatives.”

Among other things, the document states that the zoning code changes do not cut short the public input process and would not allow buildings to be any taller or bigger than stipulated in current code.