Bosnian police have confiscated the passports of four close relatives of wanted war crimes suspect Radovan Karadzic, a former Bosnian Serb leader.
Radovan Karadzic, pictured in 1995, has evaded capture for 11 years
Mr Karadzic's wife, son, daughter and son-in-law had the items and other travel documents seized on the orders of Bosnia's top international envoy.
An interior ministry spokeswoman said it would prevent them leaving Bosnia.
Mr Karadzic, Bosnian Serb leader during the 1992-95 Bosnian conflict, is wanted on genocide charges in The Hague.
His wife Ljiljana Zelen Karadzic, son Aleksandar, daughter Sonja Karadzic Jovicevic and her husband Branislav Jovicevic are suspected of helping him evade capture.
In a statement, Bosnia's international envoy Miroslav Lajcak said their passports had been seized "at the request of the International Criminal Tribunal for the former Yugoslavia and in close co-operation with relevant local law enforcement agencies".
Radovan Karadzic and Bosnian Serb wartime military commander Ratko Mladic have evaded capture for the past 11 years.
Although Mr Karadzic's family deny having any contact with him since 2002, international officials believe they have been in touch.
Nato and EU peacekeepers have regularly raided the homes of family members in the former Bosnian Serb stronghold of Pale, near the capital Sarajevo. The travel documents were handed over to police in Pale on Thursday.
The UN says Mr Karadzic's forces killed at least 7,500 Muslim men and boys from Srebrenica in July 1995 as part of a campaign to "terrorise and demoralise the Bosnian Muslim and Bosnian Croat population".
He has also been indicted over the Bosnian Serbs' shelling of Sarajevo and other crimes during the war.