JEFFERSON CITY, Mo. (AP) -- Missouri's chief elections official said Monday she was asked for photo identification at the voting booth despite a court ruling striking down the requirement.

"I'm guessing this may be happening in other parts of the state," warned Secretary of State Robin Carnahan, a Democrat who had opposed Republican efforts to mandate a photo ID in Missouri.

She said that a worker at the St. Louis Election Board asked her three times to show photo ID when she went to cast an absentee ballot Friday. Carnahan said that she tried to explain a photo ID was not necessary, but that the election worker replied that she was instructed to ask for one anyway. Carnahan said she eventually was allowed to vote without displaying a photo identification.

"To have that experience personally was very troubling," she said. The Missouri Supreme Court last month upheld a lower court's ruling overturning a law that would have required voters to show a photo ID issued by the state or federal government.