The Defense Ministry is going to investigate the authenticity of a video that allegedly shows a group of Spanish soldiers in Iraq kicking two detainees in a jail cell, government sources said on Sunday

The video, which was obtained by EL PAÍS and published on Sunday, was supposedly recorded in 2004, before Spanish troops had pulled out of Iraq, and shows five soldiers entering a holding cell and ordering two men covered with blankets to get up off the floor. When the men — who don’t appear to understand Spanish — refuse to move, three soldiers begin kicking and insulting them while two others observe from the door. A sixth soldier records the incident using a video camera.

Defense Ministry sources on Sunday called the incident “deplorable,” and said that “those who took part will be held responsible.”

In the video, the men on the floor can only be heard gasping and moaning while they are being kicked. One of the Spanish soldiers can be heard saying off camera: “Wow! They gave that one a hell of a beating already.”

The video was taken in Al Diwaniyah, where Spanish troops were deployed until 2004 before Spanish Prime Minister José Luis Rodríguez Zapatero pulled them out.

According to a soldiers’ manual, which was also obtained by EL PAÍS, the troops were instructed that “any person could be detained if it is determined he or she represents a threat to coalition forces.”

It is unclear who the detainees that appear in the 40-second video are, or why they were being held. Military sources consulted by EL PAÍS explained that the detention center in Al Diwaniyah was actually a barrack hut that had five cells located at the entrance of the troops’ headquarters. Detainees were guarded by a special unit comprised of about 30 soldiers, who were also in charge of security at the base. Nevertheless, military sources said that many of the troops who were assigned to security detail lacked specific training to deal with prisoners. At the same time, the soldiers worked in alternative shifts between patrols and guarding the base. There were incidents when some soldiers who were attacked by an individual in Iraq could find themselves keeping watch over their prisoner the following day. “The temptation to seek vengeance was great,” recalled one soldier who was stationed in Iraq.

Former Defense Minister José Bono, who served under Zapatero, said he never received any information about the alleged incident. “I cannot assure you outright that this never happened before I took over the ministry, but I am convinced that my predecessor \[Federico Trillo\] never knew about this,” Bono said.

Spanish troops were deployed in Iraq in August 2003 as part of a coalition force agreed upon by Prime Minister José María Aznar, British Prime Minister Tony Blair and US President George W. Bush. Their mission was primarily a peacekeeping one with reconstruction and humanitarian duties, according to the then-Popular Party (PP) government.

In the 10 months that Spanish troops were posted in Iraq, 11 soldiers were killed during the mission. When the Socialists were swept into office in March 2004, Zapatero ordered the troops back home in two months. His decision didn’t sit well with Washington, and relations between the United States and Spain cooled until Bush left office in 2009.

Bono recalled that he had a tense conversation with then-US Defense Secretary Donald Rumsfeld, who complained to his Spanish counterpart that he had learned about Zapatero’s order regarding Iraq from US Secretary of State Collin Powell.

The decision also caused a rift with the chief of Spanish ground troops, General Luis Alejandre, who, Bono recalled, appeared to have wanted to disobey Zapatero’s orders. Alejandre was later replaced.

After the video was released on Sunday, Defense Ministry sources pointed out that the first officials who “felt outrage about this incident” were military officials, “who, for the past 20 years have been leading international missions abroad.” The sources said that there has not “been a single complaint” about the performance or behavior of Spanish troops in the past.

Defense sources said that they will set up an investigation to determine whether or not the video is authentic, and find out who was responsible for the incident.