California lawmakers are pushing forward with legislation that would make it the first "sanctuary state" in the nation.

A proposed bill would prohibit state and local law enforcement agencies from detaining or arresting an undocumented immigrant for the purpose of federal immigration enforcement.

The state has an estimated two to three million undocumented immigrants.

"California's undocumented immigrant population is critical to the state's economic success," said Sen. Kevin de Leon, who introduced the bill to California's state senate. "That workforce contributes some $180 billion to the state's GDP."

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