Once they were enemies, commanding armies locked in deadly struggles. But together behind bars as war crimes suspects, ethnic hatreds largely evaporate among the men whom Ratko Mladic has joined at a high security U.N. jail to await his trial on genocide charges.
There's table tennis and group classes in English or computing at the detention unit built within the high stone walls of a jail on the outskirts of The Hague, according to a former detainee and a one-time employee.
Mladic was kept in isolation Wednesday while authorities monitor how he adjusts to life in the unit, said John Hocking, the Yugoslav war crimes tribunal's top administrative official.
The former general charged with orchestrating Serb atrocities in Bosnia's 1992-95 war underwent medical checks after being flown to the Netherlands on Tuesday night, Hocking said, and there will be more tests in coming days.
Mladic's family says he had two strokes during his 16 years on the run from international justice. His Belgrade lawyer tried to block the extradition by saying Mladic was too ill to go on trial.
Mladic will make his first public appearance since being arrested when he goes to court early Friday to confirm his identity. A judge will ask him if he understands the 11 charges against him and if he wants to enter pleas.
Like his old ally and political boss Radovan Karadzic three years ago, Mladic may decline to enter pleas at his first appearance, instead opting to delay a formal response by up to a month.
Because their cases are so closely interwoven _ they were indicted together in 1995 as the military and political architects of the Bosnian war's worst atrocities _ it is unlikely they will be housed in the same wing of the detention unit.
While detainees whose cases are linked are often kept apart, there is no segregation along ethnic or religious lines at the detention unit.
"The most amazing thing was that those differences were not an issue at all," said the former detention unit employee, who agreed to talk to The Associated Press on condition of anonymity because of the sensitivity of speaking about the closed unit. "Inside the unit, you saw no trace of the battles they fought outside that landed them there."
Ante Gotovina, a Croat general appealing his 24-year sentence for ethnic cleansing, reportedly passes his time painting portraits and scenes of fishing villages. Others take pottery and other crafts lessons.
The more energetic can play soccer and volleyball in a gym or even pump iron in a weight room _ although many of the detainees are, like the 69-year-old Mladic, elderly and prefer more sedentary pursuits such as chess and cooking.
"We invited each other," Bosnian Muslim Naser Oric told Bosnian television in a 2006 interview after being released from the detention unit, where he spent three years.
Oric was freed after being given a two-year sentence for failing to prevent the murder and torture of Serb captives. His convictions were later overturned on appeal.
"We Muslims from Bosnia and Kosovo celebrated our religious holidays together with the Serbs and Croats," he said. "Croats also invited Serbs, Bosniaks and Albanians to celebrate Catholic holidays, and the Serbs again invited everybody for Serb Christmas."
For those, like Mladic, who are in ill health, the unit has its own medical center and doctor as well as access to a hospital in the jail and nearby civilian hospitals.
Nonetheless, several inmates have died during their trials or waiting for them to start. Yugoslav President Slobodan Milosevic was found dead in his cell on March 11, 2006, after a heart attack.
A panel of Swedish experts reviewed the functioning of the unit after Milosevic's death and the suicide a week earlier of another key figure in the Balkan wars, the Bosnian Serb regional leader Milan Babic. It concluded that life there was far more relaxed than in normal prisons and that inmates had few complaints about their treatment.
Because many are awaiting trial or are on trial, they are presumed innocent and treated that way. They are only locked in their 15-square-meter (45-square-foot) cells at night and can roam their wings during the day.
All the one-man cells have cable TV programming from the Balkans. The accused can subscribe to newspapers from home and get regular visits from family, lawyers and consular officials.
The tribunal says the medical regime is so good that many get healthier while in custody.
Oric said the rules are fairly strict and newcomers such as Mladic are given a list of regulations when they arrive, including how to interact with other prisoners.
"In the beginning, you only follow those rules," he said. "Later, you live them, because whether you want it or not, you have to communicate with the others. They are there, you can't ignore them."