BELGRADE, Serbia-Serbian authorities were questioning seven people suspected of helping a Bosnian Serb fugitive evade justice, the war crimes prosecutor's office said Wednesday.

The seven are suspected of providing false ID documents to former Bosnian Serb police chief Stojan Zupljanin before his June arrest in Serbia, prosecution spokesman Bruno Vekaric said.

Zupljanin has been indicted by the U.N. court in The Hague, Netherlands, for allegedly overseeing prison camps where thousands of non-Serbs were killed during Bosnia's 1992-95 war.

Authorities plan to question a total of 30 people suspected of helping Zupljanin evade arrest for eight years, Vekaric said.

The spokesman said that, while at large, Zupljanin traveled freely under a false identity to a number of countries, including neighboring Montenegro and faraway Nigeria. The spokesman also said the fugitive and hidden at 27 different locations within Serbia.

Zupljanin is being held by The Hague court, but twice recently managed to telephone one of his suspected supporters in Serbia.

"We don't know how this was possible," Vekaric said, adding that The Hague court has been informed of the phone calls.

In July, authorities arrested genocide suspect Radovan Karadzic, who also was hiding here under an alias. Another suspect, former Bosnian Serb army commander Ratko Mladic, remains at large.