SREBRENICA, Bosnia-Herzegovina - Machine guns crackled and grenades exploded from dusk to dawn as the Bosnian Serb soldiers slaughtered more than 1,000 men and boys crammed into a warehouse outside Srebrenica.

But when the sun came up, a few dozen were still alive.

So the commander, nicknamed Nedjo the Butcher, called out, offering water to quench their thirst in the sweltering July heat, according to testimony from survivors and witnesses. Slowly, bloodied prisoners began to emerge from under the corpses, among them a boy clutching his grandfather's hand.

"Will they kill us too?" the boy asked.

"No," the old man whispered.

Shots rang out and the two dropped dead, along with dozens of others who had survived the night.

The carnage was among the worst of the 1995 Srebrenica massacre that killed more than 8,000 Bosnian Muslim men and boys in Europe's bloodiest civilian slaughter since the end of World War II. It is the continent's only postwar atrocity that the United Nations calls genocide.

On Wednesday, Serbia arrested eight men accused of taking part in the massacre of about 1,300 people at the warehouse on the outskirts of Srebrenica, a joint team of Serbian and Bosnian prosecutors told the Associated Press.

Chief Serbian War Crimes Prosecutor Vladimir Vukcevic said that all those arrested "are former members of a special brigade of the Bosnian Serb police."

Serbia has already put on trial men who took a group of prisoners away from Srebrenica to be killed, and in 2011 it arrested Ratko Mladic, the warlord who masterminded the slaughter, and sent him to an international criminal court in the Hague, Netherlands. But Wednesday's arrests were Serbia's first attempt to bring to justice the men who got their hands bloody in the Srebrenica massacre 20 years ago this July.

"It is important to stress that this is the first time that our prosecutor's office is dealing with the mass killings of civilians and war prisoners in Srebrenica," said Bruno Vekaric, the lead Serb prosecutor in the case.

He said Serbia was approaching a key moment in confronting its past.

"We have never dealt with a crime of such proportions," said Vekaric, Serbia's deputy war crimes prosecutor. "It is very important for Serbia to take a clear position toward Srebrenica through a court process."

Serbian prosecutors initially arrested seven suspects in predawn raids Wednesday at different locations in Serbia. They then caught the eighth suspect after an hourslong manhunt. The prosecutors said they are trying to locate more suspects who may be hiding in Bosnia, although these men were not targeted in the probe that yielded Wednesday's eight arrests.

The biggest catch was Nedeljko Milidragovic, the commander dubbed Nedjo the Butcher.