U.N. war crimes judges have sentenced a former Bosnian Serb army commander to 17 years in prison for his role in the Srebrenica massacres in 1995. Dragan Obrenovic, who admitted to playing a part in Europe's worst executions since World War II, is the second Bosnian Serb to plead guilty to helping murder more than 7,000 Muslim men and boys.

A sober-looking Dragan Obrenovic listened as Judge Liu Daqun explained why he was sentenced to 17 years in prison for crimes the judge called enormous.

"Through his acceptance of responsibility and his guilt, his sincere remorse, his substantial cooperation with the prosecution and his character, Dragan Obrenovic has mitigated his sentence," said Judge Daqun.

Obrenovic pleaded guilty to one count of persecution earlier this year and agreed to testify against his former colleagues. In exchange, prosecutors dropped all the other charges against him, including genocide.

Citing his cooperation, remorse, and admission of the facts, prosecutors had asked judges for a sentence of between 15 and 20 years. Judges agreed with the recommendation, calling Obrenovic's acceptance of guilt unreserved and unqualified, his remorse genuine and his testimony against his former officers truthful and detailed.

This is in sharp contrast to the tribunal's decision against another Bosnian Serb army officer who was sentenced last week to 27 years in prison for similar crimes. At the time, judges seriously questioned the role of plea bargains in an international criminal court.

But in Wednesday's decision, judges found Obrenovic to be a more suitable candidate for a plea agreement. They pointed out that he gave prosecutors helpful documents and let them search his brigade's headquarters during their investigation into the crimes. In the end, Obrenovic is being held responsible less for what he did than what he didn't do.

As acting commander of the Zvornik Brigade - in the area where most of the murders took place - judges found that Obrenovic did let several of his men go to help find prisoners he knew would be executed.

But judges found that, while Obrenovic knew of what they call the murder plan, he didn't conceive of it or take many actions to further it. Judges cited his inaction - his failing to prevent his men from participating in the plan - and his not taking any steps to punish them later.

Judges noted that Obrenovic is not the only person responsible for what they called the massive crimes against Bosnia's Muslims. Emphasizing the importance of individualizing guilt, judges said others will one day face justice here for their roles in the crimes. That includes former Bosnian Serb leader Radovan Karadzic and his commander General Ratko Mladic, the two men widely seen as most responsible for Srebrenica, but who are still at large.