Croatian Gen. Ante Gotovina, right, is embraced by an unidentified Croatian war veteran upon his arrival to the airport in Zagreb, Croatia on Nov. 16, 2012. The Yugoslav war crimes tribunal overturned the convictions of two Croat generals, including Gotovina, on Friday for murdering and illegally expelling Serb civilians in a 1995 military blitz. (Nikola Solic/AP)

Two Croatian generals convicted last year by an international court in The Hague of crimes against humanity have been acquitted on appeal, raising questions about ongoing prosecutions of war crimes in the former Yugoslavia.

The acquittals were greeted with celebrations in Croatia, where thousands had prayed this week for the generals’ release.

The ruling is likely to reinforce Serbian claims that the court is politically biased, since it has long held that the ethnic cleansing of Muslims and Croats carried out by Serbs in Bosnia did constitute a joint criminal enterprise.

In Belgrade, Rasim Ljajic, the Serbian minister who serves as a liaison with the tribunal, said the court had “lost all credibility,” the Serbian news agency Beta reported.

The appeals chamber of the International Criminal Tribunal for the Former Yugoslavia (ICTY) on Friday overturned the 2011 convictions of generals Ante Gotovina and Mladen Markac for ethnic cleansing of Serb civilians in Croatia in 1995.

The court’s trial chamber found both men guilty last year, sentencing Gotovina to 24 years in prison and Markac to 18 years. But the appeals chamber, headed by Israeli Judge Theodor Meron, ruled unanimously that the convictions had relied on insufficient evidence — specifically the fact that Croatian artillery shells had fallen far from any legitimate military target.

“The trial chamber erred in concluding that all artillery impact sites located more than 200 metres from a target deemed legitimate served as evidence of unlawful attacks,” the court said in a summary of its judgment.

The acquittal brought chagrin to some in the Dutch government, as the Netherlands had publicly delayed Croatia’s candidacy for the European Union from 2002 to 2005 with the demand that it hand over Gotovina to the ICTY.

It could also have implications for other international war crimes trials, including those of Radovan Karadzic, the former Bosnian Serb president, and Ratko Mladic, the former top general of the Bosnian Serb military. They are on trial at the tribunal charged with numerous crimes against humanity, including genocide, as well as artillery attacks on civilians during the 1992-95 siege of Sarajevo.

“This is going to be an important case, adding to the jurisprudence on the particular issue of targeting of artillery attacks, what is or is not an unlawful attack,” said Nicholas Koumjian, a lawyer who has served as a prosecutor at the tribunal and at the special tribunal for Sierra Leone.

But he added that most cases of unlawful attack, such as the 1995 massacre of thousands of Bosnian Muslims in Sarajevo, involve executions or detention rather than solely artillery attacks and are therefore more easily judged.

Gotovina was the commander of the Croatian military in the southern Krajina region during “Operation Storm” in 1995, when army units drove Serbian troops, along with hundreds of thousands of Serbian civilians, out of Croatia. Markac was the head of the special police forces in the area.

Prosecutors argued that Gotovina and Markac had participated in a meeting with Franjo Tudjman, then president of Croatia, at which he deliberately planned to drive out the state’s Serbian population. They argued that this had been carried out through indiscriminate shelling and that both men bore “command responsibility” for murders, plunder and cruelty committed during the operation.

But defense lawyers argued that the meeting had been ambiguous, with no specific planning aimed at deportation of Serbs. They said the trial judges had come up with the 200-meter artillery limit on their own, though it had never been argued by the prosecution team.

“The entire prosecution was a mistake, frankly,” said Guenael Mettraux, Gotovina’s defense counsel. “The problem was that they had no evidence and decided to go ahead despite that.”

The appeals chamber agreed with Mettraux, rebuking the trial judges for relying on “circumstantial evidence” on which “no reasonable trial chamber” should have based a conviction.

Significantly, the appeals chamber reversed the judgment that Gotovina, Markac and other Croatian officials had deliberately plotted with Tudjman to deport the Serbian population. Meron wrote that the evidence was not sufficient to establish the charge of a so-called “joint criminal enterprise” aimed at ethnic cleansing.

Gotovina and Markac were released immediately and were expected to return to Zagreb via chartered jet by mid-afternoon Friday.