MEXICO CITY (Reuters) - The Mexican government on Sunday condemned the fatal shooting of a Mexican citizen over the U.S. border by a U.S. agent.

The victim was hit by a single bullet on Saturday, close to the Tomates-Veterans border crossing in Matamoros, over the river from Brownsville, Texas, Mexico's Foreign Relations Ministry said in a news release.

The shot was fired by a U.S. Border Patrol agent, the ministry said in the release.

"The Mexican government has reiterated that the disproportionate use of lethal force in immigration control is unacceptable under any circumstances," it said.

Officials for the Border Patrol were not immediately available for comment.

According to media in Brownsville, an agent reported that he had fired in response to rocks being thrown over the border.

(Reporting By Ioan Grillo; Editing by Eric Beech)