An ex-soldier in the Bosnian Serb army who participated in the execution of over 1,000 Bosniaks during the 1995 Srebrenica massacre testified this week in the trial of former Bosnian Serb president Radovan Karadzic.

Drazen Erdemovic, who served in the 10th Sabotage Detachment of the Bosnian Serb Army during the conflict, has testified in numerous previous trials at the Hague tribunal.

In 1998, Erdemovic pleaded guilty to murder as a war crime and was sentenced to five years in prison for participating in executions at the Branjevo farm on July 16, 1995.

At one point during this week’s cross-examination, Karadzic – who represents himself in the courtroom – asked the witness why he decided to speak out and tell prosecutors his story.

“Why did I decide that, Mr Karadzic? I decided that because I realised my life had been ruined on that day, and because of all the persons who were victims on that day,” the witness replied.

Erdemovic has estimated that he personally killed about 70 of the approximately 1,200 men who were gunned down at the farm that day. He has said he carried out the executions because he was threatened with death if he refused the order.

The eastern Bosnian enclave of Srebrenica fell to Serb forces on July 11, 1995, and in the days that followed, some 8,000 Bosniak men and boys were killed at various sites in the surrounding area. The massacre has been classified as genocide by both the Hague tribunal and the International Court of Justice.

Karadzic, who was Bosnian Serb president from 1992 to 1996, is charged with individual and superior responsibility for Srebrenica, as well as for the 44-month siege of Sarajevo that left nearly 12,000 people dead.

The indictment – which lists 11 counts in total – alleges that he was responsible for crimes of genocide, persecution, extermination, murder and forcible transfer which “contributed to achieving the objective of the permanent removal of Bosnian Muslims and Bosnian Croats from Bosnian Serb-claimed territory”.

Karadzic was arrested in Belgrade in July 2008 after 13 years on the run. Witness testimony in his trial got under way in April 2010.

According to the prosecution’s summary of Erdemovic’s evidence, the witness left his military base in Vlastenica on the morning of July 16, 1995 with seven other members of his unit. They stopped in Zvornik, and a lieutenant-colonel in Bosnian Serb army uniform and two military policemen followed the group by car to the Branjevo farm.

Once they arrived, the lieutenant-colonel spoke with Brano Gojkovic, who was in charge of the unit in which Erdemovic was serving. As prosecuting lawyer Christopher Mitchell told the court, Gojkovic then informed the group that buses carrying civilians from Srebrenica would be arriving, and these people were to be killed.

“The first group of ten civilians who were taken off the bus were blindfolded and had their hands tied behind their backs,” said Mitchell, reading from the summary. “They were escorted to a site about 100 to 200 metres away from the bus, and lined up in a row with their backs to the execution squad.”

Gojkovic then gave the order to shoot, and the witness and seven other members of the unit opened fire with automatic rifles. This pattern continued from late morning until three or four in the afternoon, the prosecutor said.

One of the soldiers in the unit, Aleksandar Cvetkovic, apparently suggested that they should use machine guns to kill the men because it would be faster.

“However, a quarrel soon broke out over the use of the machine gun because it was causing severe injuries to civilians without actually killing them,” Mitchell said.

Cvetkovic was arrested in Israel in January 2011 after Bosnia filed a request for his extradition. The case is currently pending before Israel’s Supreme Court.

During the executions, another group of soldiers arrived from Bratunac to join in, the prosecutor said, and they “kicked, punched and cursed the prisoners, and also beat them with rifle butts and metal bars they found on the farm”.

The lieutenant-colonel eventually came back and said there were an additional 500 prisoners at the Pilica cultural centre who also had to be executed, but Erdemovic and some other soldiers refused to go.

Instead, the soldiers from Bratunac went to the cultural centre to kill the prisoners and Erdemovic and his fellow soldiers were instructed to meet the lieutenant-colonel at a coffee bar nearby. When the witness arrived there, he saw several dead bodies in front of the culture hall and heard gunfire and explosions, the prosecutor stated.

Erdemovic told the court that he went to Serbia in 1996 and decided to give an interview to a journalist from ABC News about what he had seen and done. He was arrested by Serbia’s state security services shortly thereafter, he said.

Prosecuting lawyer Mitchell presented the witness with an order that Karadzic issued on March 23, 1996, about creating a “mixed expert commission” to investigate “the alleged discovery of two decomposing bodies found on the scene of earlier battles with the Muslim side in the Pilica area”.

“To the journalist, or in the statement to the Serbian [police], did you describe events at Branjevo as battle or combat?” Mitchell asked the witness.

“No,” Erdemovic said.

“Were you engaged in conflict with the Muslim men killed at Branjevo farm on July 16, 1995?” Mitchell asked.

“No, they were not armed,” the witness said.

When it was Karadzic’s turn to cross-examine the witness, he spent a great deal of time going over the exact timeline of the day and how long everything took.

“How long did it take for the ten blindfolded individuals to get from the bus to the execution site?” Karadzic asked.

“Mr Karadzic, it wasn’t possible for me to follow all this, to keep [an] eye on my watch to see how long it took,” Erdemovic said.

“So the eight of you opened fire on the ten of them, isn’t that correct?” Karadzic asked.

“I opened fire on the person in front of me, Mr Karadzic,” the witness replied.

“So if you opened fire on the person in front of you, then you killed five individuals from that bus, correct?” Karadzic asked.

“Mr Karadzic, I didn’t count the number of people I killed,” Erdemovic responded. “If you think I killed five of them, that is your opinion.”

“The prisoners had their backs turned to you, is that correct?” Karadzic asked at one point.

“Yes,” the witness said.

“What was the purpose of blindfolding them in that case?” Karadzic asked.

“They already had these blindfolds on in the buses and as far as I can remember, in the first bus their hands were tied behind their backs,” Erdemovic said. “I don’t know who took this decision or why they decided [the men] should be blindfolded.”

Later, Karadzic asked the witness whether he had fired at the prisoners “with the intention of destroying the Muslims as an ethnic group in Bosnia”.

“No, Mr Karadzic,” the witness said.

“Why was this killing taking place; what were the intentions involved?” the accused asked.

“I don’t know exactly, Mr Karadzic, who was killing with what intentions in mind,” Erdemovic said. “As far as I could see, some persons really enjoyed torturing others.”

The trial continues next week.

Rachel Irwin is an IWPR reporter in The Hague.