BELGRADE, Serbia — Four paramilitaries seen in a video gunning down Bosnian Muslims near Srebrenica in 1995 were convicted of war crimes against civilians yesterday by Serbia’s War Crimes Court.

It was the country’s first court ruling related to the systematic killings of up to 8,000 Muslim men and boys in Srebrenica in the final months of the 1992-95 war in Bosnia — Europe’s worst atrocity since World War II.

Trials of Serbs in Serbia have only become possible since the 2000 ouster of President Milosevic, and the Srebrenica case has been a key test of the ability of Serbia’s judiciary to deal with wartime atrocities.

The four Serbs found guilty yesterday were seen in a video that surfaced in June 2005 when it was shown at the war crimes trial of Milosevic before the U.N. tribunal for the former Yugoslavia.

The video shows members of a notorious Serbia paramilitary unit known as the Scorpions.

The footage, recorded by a Scorpions member who apparently believed it would never become public, showed the men taking Bosnian Muslim civilians from a truck with their hands tied and lining them up on a hillside before spraying them with machine gun fire.

The unit’s commander, Slobodan Medic, and a fellow paramilitary were each sentenced to 20 years in prison — the maximum sentence possible — while the only defendant who admitted to shooting the victims, Pero Petrasevic, was sentenced to 13 years in prison. Another Scorpions member, accused as an accomplice, was sentenced to five years in jail, while a fifth was cleared.

The verdict followed a February decision by the U.N.’s highest court, the Netherlands-based International Court of Justice, clearing Serbia of direct responsibility for the Srebrenica genocide.

But the footage, widely broadcast in Serbia as well as in Bosnia, shocked some Serbians who were in denial about the wartime atrocities committed by the Serb forces.

Of the six victims in the video, four were shot in the back. Two others were ordered to carry the bodies into a barn where they, too, were killed.