Mexico is demanding the United States conduct an investigation following the shooting death of a man who allegedly tried to cross the border into the U.S. illegally.

U.S. authorities say a border patrol agent shot and killed a suspected smuggler of illegal immigrants on Wednesday at the fence that separates the southern U.S. city of El Paso, Texas, from Mexico. U.S. authorities say the man tried to hit the agent with a rock and was holding bolt cutters in his other hand.

Mexico's Foreign Ministry issued a statement saying that the Mexican government opposes the use of lethal weapons "in situations that do not represent a proportionate risk."

The incident is the latest of several border shootings that have strained relations between the United States and Mexico.

Some information for this report was provided by AP and Reuters.