(CNN) -- Police in Serbia have arrested a man suspected of being former Serbian military commander Ratko Mladic, the highest-ranking war crimes suspect still at large from the Balkan wars of the 1990s, Serbia's B92 radio reported Thursday.
Police are doing DNA tests on the man to determine if he is Mladic, the radio station reported, citing a leading Croatian newspaper. The radio station said it "contacted the police, but was told only that an indentity check and DNA analysis were 'ongoing.'"
CNN has not confirmed the report, but Serbian President Boris Tadic's office announced a surprise press conference for Thursday afternoon, shortly after the reports first appeared.
Mladic, 69, is wanted on charges of genocide, extermination and murder, among other charges, by the International Criminal Tribunal for the former Yugoslavia.
The tribunal accuses him of "direct involvement in the genocide committed after the fall of Srebrenica in July 1995," and the killing of "close to 8,000 men and boys following the fall of this enclave."
The massacre of the Muslim men and boys is thought to be the largest individual slaughter in Europe since the end of World War II.
The 1992-95 Bosnian war was the longest of the wars spawned by the breakup of Yugoslavia in the early 1990s.
Backed by the government of then-Yugoslav President Slobodan Milosevic, Bosnian Serb forces seized control of more than half the country and launched a campaign against the Muslim and Croat populations.
Mladic has been on the run since the war in Bosnia and Herzegovina ended in 1995.
His former boss, Radovan Karadzic, was arrested in July 2008 and is now on trial in The Hague. Karadzic, the president of Serbia during the war, was removed from power under the Dayton Peace accords that ended three years of brutal fighting.
He went into hiding and was working in an alternative medicine clinic in Belgrade, right under the noses of the authorities, when he was captured.
He had grown a full white beard and long hair.
He has been insisting on defending himself at The Hague. Prosecutors accuse him of deliberately obstructing the trial with delaying tactics, and judges have threatened to impose a defense lawyer on him if he does not cooperate.
Milosevic was toppled in 2000 and put on trial at The Hague. He died in jail in 2006 before the trial came to an end.