CNN

(CNN) - An Arab-American civil rights group sent a letter to Barack Obama asking him to personally respond to reports Wednesday that two women were denied the opportunity to stand behind the presumptive Democratic presidential nominee on stage at a campaign event because they were wearing traditional Muslim head scarves.

The Politico, a Washington-based Web site devoted to politics, reported Wednesday that Obama campaign volunteers refused to allow two women attending a rally in Michigan Monday the chance to stand behind the presumptive Democratic presidential nominee. The paper said one woman was asked to remove her head scarf, and cited political considerations in keeping the other from joining Obama on stage.

The Obama campaign moved quickly Wednesday to defuse the situation by stating the incidents did not reflect campaign policy. "It is offensive and counter to Obama's commitment to bring Americans together and simply not the kind of campaign we run. We sincerely apologize for this behavior," said spokesman Bill Burton, in a statement sent to reporters Wednesday afternoon

The e-mail also contained photos of women in Muslim head scarves attending Obama rallies and standing behind the candidate on stage.