A coalition of environmental and Native American groups on Monday sued the California Department of Fish and Game over permits issued to build 21,000 homes on Los Angeles County's last major tract of undeveloped land.

The coalition, which filed the suit in San Francisco County Superior Court, alleges that fish and game officials violated state environmental codes in granting permits Dec. 3 for the controversial Newhall Ranch development.

"It is appalling that the Department of Fish and Game, the trustee for all of California's wildlife, approved ecological destruction on this scale," said John Buse, a senior attorney for the Center for Biological Diversity, one of the plaintiffs. "Far less damaging options were available, but the department brushed them aside."

Fish and Game spokesman Andrew Hughan said he could not comment because the department has not yet seen the lawsuit, but in an earlier statement department officials said the approved plan will preserve 70 percent of the nearly 14,000-acre area as natural open space.

That space includes preserves to protect 76 percent of the rare San Fernando Valley spineflower and 93 percent of the Santa Clara River corridor.

Developers must also establish a $6 million endowment for preservation efforts.

"Hundreds of people, including biologists, botanists, hydrologists and other scientists, worked together to shape this biologically innovative project, and the end result ensures the protection of this site's unique natural resources," said Ed Pert, South Coast regional manager.