Serbian police arrested eight people on charges related to the Srebrenica massacre 20 years ago, which took place in the aftermath of the breakup of Yugoslavia.

The detainees are to be charged with killing 1,000 to 1,300 people in 1995, during the ethnic war in the region, the Serbian War Crime Prosecutor’s office said.

“This is the first case in the history of Serbian justice where such a large number of victims are involved,” Novak Vuco of the office’s press department told The Wall Street Journal.

Mr. Vuco said that trials could start by the end of this year.

Yugoslavia split into independent republics in the 1990s, leaving ethnic minorities scattered throughout the newly formed countries.

The eight individuals were detained on Wednesday in Serbian cities and towns, mostly in Belgrade and Novi Sad.

In December, Serbia and Bosnia-Herzegovina arrested 15 people suspected of torturing and killing a group of people during the conflict 20 years ago.

The countries of the former Yugoslavia have for the most part reconciled their differences. Slovenia and Croatia have since become members of the European Union while Serbia is a candidate.