Montenegro extradited to Bosnia on Friday an ethnic Serb suspected of taking part in the killing of more than 100 Muslim civilians at the start of the country's 1990s war, the prosecutors said.
Sarajevo suspects Slobodan Knezevic of "personally participating in the war crime committed in Miska Glava" near the northwestern town of Prijedor, a prosecutors' statement said.
In June 1992, Bosnian Serb forces detained in the village around 120 Muslim civilians who were later shot dead.
Knezevic, 50, is suspected of taking part in both the detention and killing of the prisoners, the statement said.
He was arrested in Montenegro in December.
Fellow Bosnian Serb Milorad Obradovic, suspected of taking part in the same crimes, was arrested in January in Germany.
Nine wartime members of Bosnian Serb military and police forces accused in connection with the same atrocities have been on trial at a Sarajevo court since April last year.
Bosnian Serb forces killed around 3,200 people in the Prijedor area during the war.
The remains of more than 770 of them have still not been found, according to Bosnia's Missing Persons Institute.
Around 100 mass graves have been uncovered in the area, the latest of them discovered in September around 140 kilometres (90 miles) southeast of Prijedor.
The remains of at least 86 people were exhumed from the grave in Koricanske Stijene.
Bosnia's 1992-1995 war between its Croats, Muslims and Serbs broke out as Yugoslavia collapsed and claimed some 100,000 lives.