The National Guard members were handed over by their superiors to prosecutors in the northern state of Chihuahua following the woman's death on Tuesday.

Her husband was also wounded during the protest at the La Boquilla dam.

President Andres Manuel Lopez Obrador said he regretted the death, but defended the military.

"The Guard acted very well because, first, they were outnumbered by protesters and even though they had weapons, they decided not to use them," he told reporters.

Lopez Obrador says that although Mexico is obliged to supply the United States with water under a 1944 treaty, it ensures that it does not affect supplies on its side of the border.

Lopez Obrador and Chihuahua state governor Javier Corral accuse each other of politicizing the issue of the dam.