The post -- which was taken down soon after it was put up Wednesday -- showed a wood carving-style image of a slave auction with the words "pro choice" beneath it and a caption that read: "Against slavery? Don't buy one."
Party executive committee members said in the apology the organization was "very sorry that something so clearly improper (either intended or in poor taste) ever made it to our page," but officials said it would be difficult to determine who posted it because so many people are registered as administrators for the page.
The statement said the administrative rights would be revoked until the responsible party is identified.
Minnesota Democratic-Farmer-Labor Party Chairman Ken Martin told the St. Paul Pioneer Press the image was "disgusting and reprehensible."
Brett Buckner, a former head of the Minneapolis NAACP, told KSTP-TV, St. Paul, taking the post down and issuing an apology was a "step in the right direction" for the county GOP.
"Unfortunately, these things are still around in society, but many, including some of our friends in the GOP, are stepping up and doing the right thing and denouncing it," he said.
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