Bosnia's war crimes court has convicted four former Bosnian Serb soldiers for participating in the execution of hundreds of Srebrenica Muslims during the country's 1992-95 conflict, sentencing them to a total of 142 years in prison.
About 800 captured Muslim Bosniaks were shot and killed at Branjevo military farm, near Srebrenica.
Judge Mira Smajlovic said the four soldiers carried out the crime in "an organised and systematic" manner.
It was one of several sites where more than 8,000 such victims were killed in 1995 in what became known as the Srebrenica massacre and a major development in the Bosnia war.
The court on Friday handed down its stiffest sentence yet when it jailed a former elite Bosnian Serb soldier Stanko Kojic for 43 years for his part in the atrocity.
Kojic, a member of the Bosnian Serb 10th Sabotage Detachment, was convicted of crimes against humanity for taking part in the July 16 killing at Branjevo farm, located about 70km north of Srebrenica.
Two other members of the same unit, Slovenian Franc Kos and Bosnian Serb Zoran Goronja, both got 40 years, while a third man, Vlastimir Golijan, received a 19-year prison sentence.
"The panel of judges has established that the accused committed a crime against humanity," Smajlovic said.
The four were however acquitted on genocide charges when the court found it had not been proven they had "genocidal intent".
Smajlovic described how during the bloody killing spree the members of the 10th Sabotage Detachment took breaks to eat and drink beer.
"Their attitude toward the killings can be best understood when one knows they even took a break to have lunch and drink beer in the meadow full of corpses, while other prisoners looked on from the buses," waiting for their turn to be murdered, Smajlovic said while reading the verdict.
'Organised and systematic'
During the trial, Kos, one of the commanders of the unit, admitted to having taken part in the massacre, describing how the detainees had been brought to the execution site in buses.
"They were heading calmly towards the execution site and lined up," he told the court.
"We killed them by shooting them in the back," he added. He estimated that his platoon had executed about 300 people, before being replaced by other soldiers.
Kos and Kojic also shot wounded prisoners in the head using pistols to "make sure no one will survive," the judge said.
The 10th Sabotage Detachment, which also included non-Serb mercenaries, was founded by former Bosnian Serb army chief Ratko Mladic.
Mladic is currently on trial for genocide at the International Criminal Tribunal for the former Yugoslavia (ICTY) in The Hague.
Srebrenica was the worst such atrocity in Europe since World War II and was ruled a genocide by both the ICTY and the UN's top court, the International Court of Justice.
Other Bosnian Serb soldiers have been convicted of taking part in the massacre by Bosnia's court and the ICTY, while several other suspects remain at large.