We expect Serbian authorities to bring to justice all individuals at all levels who are responsible for their deaths without further delay. This also remains a high priority on our bilateral agenda with Serbia,“ U.S. State Department Spokeswoman Victoria Nuland said in a release.

The Higher Court in Belgrade acquitted on Wednesday Sreten Popović and Miloš Stojanović who were charged with aiding the murder of the Bytyqi brothers in the village of Petrovo Selo in 1999.

“The U.S. remains deeply concerned that, to date, no individuals have been convicted for the 1999 killings of U.S. citizens Agron, Ylli, and Mehmet Bytyqi. While attempting to save the lives of a Roma family from Kosovo, the Bytyqi brothers were detained without due process by Serbian authorities and suffered an execution-style death,” reads the State Department statement.

The Bytyqi brothers arrived in Kosovo in order to join the ethnic Albanian so-called Kosovo Liberation Army (KLA) during the 1999 war. The were arrested after the war on charges of illegally crossing the border from Albania, and sent to jail in the town of Prokuplje after being found guilty on misdemeanor charges.

According to the indictment, Stojanović arrested the Bytyqi brothers after they had been released from prison in Prokuplje on Popović’s orders.

He then took them to a Serbian police (MUP) training center in Petrovo Selo where he detained them. The following day, on July 9, 1999, they were taken by Serbian police officers who killed them.

The Bytyqi brothers’ remains were found in a mass grave near the MUP Special Anti-Terrorist Unit (SAJ) headquarters in Petrovo Selo in 2001.

Explaining the verdict on Wednesday, the judge stated that the court had only determined that the suspects had taken the Bytyqi brothers from prison, where they served their sentence for a misdemeanor, and then put them in a room without any adequate living conditions.

“This could possibly be torture or inhumane treatment but it is unclear why the prosecutor has not charged them with it. It is also not clear, as it is written in the indictment, what was the trial in which the Bytyqi brothers were deprived of their right to a fair trial,” the judge added.

The War Crimes Prosecution has the right to appeal and the Appellate Court is obligated to make a final decision in the case bearing in mind that it no longer has the right to quash the initial verdict.