Mexico: Video of soldiers killing detained man sparks uproar

A military convoy patrols a road near Palmarito Tochapan in Puebla State, Wednesday, May 10, 2017. A video released by Mexican media outlets Wednesday appears to show a soldier executing a civilian lying face down in the street in Palmarito Tochapan with a shot to the back of his head. The footage purportedly depicts a portion of the military's encounter with fuel pipeline thieves in that the government said left 10 dead. (AP Photo/Rebecca Blackwell) (The Associated Press)

Bullet holes mark a wall at an intersection where a video released by Mexican media outlets appeared to show a soldier executing a civilian lying face down in the street with a shot to the back of his head, in Palmarito Tochapan, Puebla State, Wednesday, May 10, 2017. The footage purportedly depicts a portion of the military's encounter with fuel pipeline thieves in that the government said left 10 dead. (AP Photo/Rebecca Blackwell) (The Associated Press)

Bullet holes mark a window at a home near an intersection where a video released by Mexican media outlets appeared to show a soldier executing a civilian lying face down in the street with a shot to the back of his head, in Palmarito Tochapan, Puebla State, Wednesday, May 10, 2017. The footage purportedly depicts a portion of the military's encounter with fuel pipeline thieves in that the government said left 10 dead. (AP Photo/Rebecca Blackwell) (The Associated Press)

A video that purportedly shows Mexican troops detaining and shooting dead an apparently wounded man is drawing criticism and calls for an investigation.

The security camera footage first published by Diario Cambio is purportedly related to incidents May 3 in Puebla state, where the military has said clashes with alleged fuel pipeline thieves left 10 people dead.

In the video heavily armed agents are seen firing on a car and detaining at least three people. One is seemingly wounded and is dragged by soldiers. As he lies face-down on the ground, a soldier appears to fire a close-range gunshot at his head.

In a statement Wednesday, the Defense Department said military and civilian authorities will investigate the video's authenticity and whether a crime was committed.