(CNN) The United Methodist Church is investigating voting irregularities at its General Conference, which decided last month to reinforce policies that bar openly gay clergy and same-sex marriage.

A probe by church organizers and an independent auditor looked into the credentialing process for the more than 800 Methodist delegates who voted at the conference, held inside a football stadium in St. Louis.

A "very limited number" of ineligible delegates were able to obtain voting credentials, the Rev. Gary W. Graves, secretary of the General Conference, said in a statement . He did not give a more specific number.

"We take the integrity of the legislative process very seriously, and the breakdown in the process is troubling," said Graves, who added that the matter is being referred to the church's Commission on the General Conference.

Methodist leaders are also consulting with the parliamentarian during General Conference about whether the irregularities affected the church's legislative voting.

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