The incident took in the capital Brasilia late last year, when three Marines on a US Embassy security team and one embassy staff member pushed a female escort out of a car after a dispute over payment. The woman broke her collarbone in the incident, the Associated Press reported.
"There were at least two women with the Marines outside a nightclub," a US defense official said on condition of anonymity.
The official added it appears that one of the women started a fight in a vehicle, then she was removed from the car, and when she tried to re-enter, she fell to the ground and was injured.
He also said that no charges were filed by Brazilian authorities.
Another defense official said the embassy staff member was a supervisor. The embassy tracked the woman down and paid for her medical expenses.
Defense Secretary Leon Panetta said Tuesday that the four people have received disciplinary action.
Panetta, speaking to reporters in Brasilia, said the Marines were pulled out of the country. Two had their ranks reduced, and the embassy staffer was removed from his post.
The US defense secretary noted that he had "no tolerance for that kind of conduct. Where it takes place, you can be sure that we will act to make sure that they are punished and that that kind of behavior is not acceptable," he said.
This is the second such incident involving American security personnel abroad that has surfaced this month.
US Secret Service and military personnel took as many as 21 women back to their hotel rooms on the nights of April 11-12, just before US President Barack Obama’s arrival in Cartagena, Colombia, to attend the sixth Summit of the Organization of American States (OAS).
The scandal erupted after a fight over payment between a Colombian escort and a secret Service employee spilled into the hallway of the Hotel Caribe the following morning, leading to the involvement of the local police.
The Colombia sex scandal has turned into an embarrassment for the US administration and overshadowed Obama's participation at the OAS summit.