Biljana Plavsic served her sentence in a Swedish prison
Former Bosnian Serb President Biljana Plavsic has been freed from prison after serving six years for war crimes.
The UN war crimes court granted her early release for good behaviour from the 11-year sentence it passed in 2003.
Plavsic, 79, known as the "Iron Lady", was the highest-ranking official from the former Yugoslavia to have pleaded guilty for her part in the Bosnian War.
She left Sweden as soon as she was released from prison there, officials said, and travelled to Belgrade.
Plavsic arrived in the Serbian capital, where she has a home, accompanied by Bosnian Serb Prime Minister Milorad Dodik.
"I am happy to be free after nine years," she told reporters.
She blew a kiss to waving reporters before disappearing through the front door of her house.
The BBC's Mark Lowen in Belgrade says that Plavsic's release has prompted a mixed reaction in Serbia.
"It's great news, she has right to live because she didn't do anything bad. She only protected her people. Nothing else," one Belgrade resident said.
Another one said: "I'm just not happy about it. People like her should be in prison longer than she has been."
Some in Serbia worry that Plavsic will now be glorified by the ultra-nationalists for her war time role, our correspondent says.
He adds that the government in Belgrade is urging people not to focus on her release, warning that the international community will be watching how Serbs react.
Plavsic was indicted by The Hague tribunal in 2001 for genocide and other crimes during the Bosnian war in the 1990s.
She later pleaded guilty to persecution of non-Serbs in return for all the other charges being dropped and a shortened sentence of 11 years.
When plans for Plavsic's early release were announced in September, the president of The Hague tribunal cited good behaviour and "substantial evidence of rehabilitation".
During the Bosnian war, Plavsic was known as the "Serbian Iron Lady" because of her hardline nationalism and rabidly anti-Muslim views.
She was also one of the closest allies of former Bosnian Serb leader Radovan Karadzic, himself accused of war crimes.
Her release came on the second day of his trial in The Hague, which Mr Karadzic is boycotting.
In prison, Plavsic wrote a book describing the events that led up to the Bosnian war.
In the book, I Testify, published in 2005, she called on Mr Karadzic and General Ratko Mladic to surrender to the UN court in The Hague.
She described Mr Karadzic as a "coward", but Gen Mladic as a "great man" who "should defend the Serb people and his soldiers before The Hague tribunal even at the cost of sacrificing himself".
Mr Karadzic was captured in July 2008, but Gen Mladic remains at large.