The U.S. Justice Department on Thursday issued subpoenas to California officials in an escalation of its scrutiny of local election administration. The subpoenas were being issued by all four U.S. attorneys in California, according to a person familiar with the matter who insisted on anonymity to discuss an ongoing investigation. The move follows a federal judge’s appointment of a special master earlier Thursday to evaluate claims by the Trump administration that California has about 20,000 noncitizens on its voter rolls, less than 24 hours after he rejected the Justice Department’s demand that California sequester the ballots until citizenship can be verified.