Louisiana's Republican Party has filed a complaint against Democratic U.S. Sen. Mary Landrieu with the Senate's ethics committee about her use of private chartered planes.

The complaint, filed Tuesday by party executive director Jason Dore, accuses Landrieu of violating federal law by billing her taxpayer-funded Senate office for flights to attend campaign fundraisers.

Landrieu is seeking re-election on the Nov. 4 ballot. She ordered a complete review of all flight payments after Republicans questioned whether nearly $9,000 in reimbursements revealed a pattern of improperly using taxpayer dollars to pay for campaign events.

The incumbent senator called the payments a "bookkeeping mistake." Dore called Landrieu a Washington insider who has violated the public's trust.

GOP leaders have questioned at least $20,000 in flights as improperly billed to Landrieu's Senate office.

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