Opponents of same-sex marriage came out swinging in response to a California judge's ruling Monday that struck down state laws prohibiting gays and lesbians from marrying.

"This is a crazy ruling by an arrogant San Francisco judge who apparently hates marriage and the voters," said Randy Thomasson, the executive director of Campaign for California Families, one of the organizations fighting to keep California's existing marriage laws intact.

The Rev. Louis P. Sheldon, chairman of the anti-gay Traditional Values Coalition, called it "yet another example of judicial tyranny."

In his ruling Monday, San Francisco County Superior Court Judge Richard Kramer said that denying gay couples the right to marriage amounts to a form of gender discrimination, thus violating the state Constitution's equal protection clause.

Kramer's decision was stayed for 60 days to allow time for appeals. It has been a foregone conclusion all along that the case will ultimately be appealed all the way to the California Supreme Court.

From the moment the decision was announced, supporters of same-sex marriage have been rejoicing.

"I am so happy that my parents can finally get married," said Ericka Sokolower-Shain, the 15-year-old daughter of Karen Shain and Jody Sokolower, two of the co-plaintiffs in the case.

Leaders on both sides of the debate warned that the ruling would further radicalize anti-gay groups.

"Our opponents are trying to stampede people into making hasty, ill-informed decisions out of prejudice, ignorance, anxiety, discomfort or fear," said Evan Wolfson, executive director of Freedom to Marry, a national organization dedicated to marriage equality for lesbians and gays.

California Assemblyman Ray Haynes, a Republican from Southern California, predicted the ruling would fire up efforts to amend the state Constitution to ban same-sex marriage, as 13 other states did last year.

And Bruce Hausknecht, a legal analyst for Focus on the Family, said the ruling adds credence to his organization's call for amending the federal Constitution.

"Until the U.S. Constitution is amended to protect marriage, we will have to continue to fight to protect marriage from these kinds of challenges," he said.

Mathew Staver, president of the anti-gay Liberty Counsel, told the Associated Press that Judge Kramer's ruling "will be gasoline on the fire of the pro-marriage movement in California as well as the rest of the country."

The ruling is significant in part because California is the most populous state in the nation, with the largest number of same-sex couples, according to the U.S. Census Bureau.

California already has one of the nation's most sweeping domestic partner laws. Currently, Massachusetts is the only state where same-sex marriage is legal.