A Bosnia-based international agency for missing persons said Friday it had identified 2,000 victims of the Srebrenica (search) massacre whose bodies were found in mass graves in Bosnia.

The International Commission on Missing Persons (search) has a list of 7,800 persons who disappeared in the worst massacre of civilians in Europe since World War II. Bosnian Serb forces overran the Muslim enclave of Srebrenica in July 1995 and executed thousands of men and boys.

Rifat Kesetovic, chief forensic pathologist of the organization, signed the 2,000th Srebrenica-related death certificate at a morgue in the northern city of Tuzla (search).

"We are proud to have passed this landmark, but there are still around 6,000 missing victims from Srebrenica and we are working hard to find them, to identify them and to return them to their families," Kesetovic said.

The missing persons' commission runs one of the most sophisticated DNA laboratories in the world. Its experts create DNA profiles for victims from remains and then match them with DNA taken from the blood of family members who reported their relatives as missing.

The ICMP pioneered the use of DNA as a means of identifying large numbers of missing persons, achieving its first DNA match between mortal remains found in a mass grave and family members of a missing victim, a boy from Srebrenica, in November 2001.

Also Friday, Serbian police arrested a fifth suspect incriminated in the Srebrenica killings in a 1995 execution video of Muslim prisoners, Belgrade media reported.

The suspect, identified as Branislav Medic, 42, was said to have been a former member of the notorious Serb paramilitary unit known as the Scorpions, the independent Beta news agency reported, citing Serbian police.

The amateur footage, apparently shot by the Serb troops, shows six prisoners in civilian clothing taken from a truck, hands tied and then lined up on a hillside. Then, four are shot one by one in the back. Two others are ordered to carry the bodies into a nearby barn before they, too, are killed.

The footage forced Serbian politicians to acknowledge that the Serb troops committed war crimes against civilians during the Balkan wars of the 1990s.

After the video was also broadcast by Serbian television channels, police arrested four former Scorpion members, all seen in the video.