"My efforts are aimed at improving the cooperation and ensuring that police do their work," Ostojic told a press conference after attending a conference on the fight against cyber crime.

The conference was also attended by Serbia's Interior Minister Ivica Dacic, Macedonia's Gordana Jankuloska, Montenegro's Ivan Brajovic, Turkey's Idris Naim Sahin, and Bosnian Security Minister Sadik Hametovic.

Ostojic said that, given his specific position as minister who is not directly involved in investigations, during his bilateral talks with other ministers he did not discuss specific cases, including the murder of a Mexican woman in the southern coastal city of Split.

"Rest assured that I will support all forms of police cooperation in the region and ensure that they can do their job," Ostojic said.

Dacic described police cooperation in the region as very good. He confirmed that the Serbian police had provided logistical support for Wednesday's Bosnian police operation during which 25 persons were arrested on suspicion that they were members of two criminal groups that had committed a series of murders and robberies.

According to available information, one group was led by Darko Elez and the other by Naser Keljmendi, who escaped arrest.

Ahmetovic confirmed that police were looking for Keljmendi and that they knew his whereabouts, but declined to reveal details. He only said that Keljmendi was on a US black list and that an international warrant for his arrest was expected to be issued soon.

Keljmendi's Sarajevo lawyer told local media that Keljmendi had called him on the phone on Wednesday, apparently from Montenegro, because the number had the Montenegrin prefix. "No one was looking for him. If they had, Keljmendi would have reported to the police himself," lawyer Midhat Koco said.

The Montenegrin minister of the interior denied that Keljmendi was in Montenegro. "Police have no such information, and I am talking about the information that has been verified," Brajovic said.