Thousands of voters in Georgia's third-largest county who received their absentee ballots late will not get an extension to return them, the state's highest court decided on Monday.

Cobb County, just north of Atlanta, didn't mail out absentee ballots to some 3,400 voters who had requested them until late last week. Georgia law says absentee ballots must be received by the close of polls on Election Day. But a judge in a lower court ruled last week that the ballots at issue could be counted if they're received by this Friday, three days after Election Day, as long as they were postmarked by Tuesday.

The Georgia Supreme Court ruling means the affected Cobb County residents must vote in person on Election Day, which is Tuesday, or bring their absentee ballots to the county elections office by 7 p.m. that day.

The high court ruling instructs county election officials to notify the affected voters by email, text message and in a public message on the county election board's website. And it orders officials to keep separate and sealed any ballots received after the Election Day deadline but before 5 p.m. Friday.

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Board of Elections Chair Tori Silas said the board will comply with the Supreme Court order, but it's still up in the air whether ballots received after Election Day will be counted. The order only addressed a motion for a stay, so election officials will have to wait for the court's final ruling to see whether votes received after Tuesday will be counted, she said in a statement.

To deliver the ballots on time, election officials in Cobb County were using U.S. Postal Service express mail and UPS overnight delivery, and sending the ballots with prepaid express return envelopes. The Board of Elections said that more than 1,000 of the absentee ballots being mailed late were being sent to people outside of Georgia.

Silas last week blamed the delay in sending out the ballots on faulty equipment and a late surge in absentee ballot requests during the week before the Oct. 25 deadline.

The original ruling extending the deadline stemmed from a lawsuit filed by the American Civil Liberties Union and the Southern Poverty Law Center on behalf of three Cobb County voters who said they had not received absentee ballots by mail as of Friday.