Sudanese President Omar al-Bashir has returned to Khartoum from South Africa, avoiding arrest over war crimes charges on an international warrant.
Mr Bashir flew out of South Africa despite an order barring him from leaving while a Pretoria court decided whether to arrest him on charges issued by the International Criminal Court.
Mr Bashir was visiting Johannesburg for an African Union (AU) summit.
An ICC official said the failure to arrest Mr Bashir was "disappointing".
"We still remain quietly optimistic and determined to see justice done in this case," deputy prosecutor James Stewart told the BBC.
The Pretoria High Court issued an order for Mr Bashir's arrest hours after his aircraft left the country.
A South African judge, Dunstan Mlambo, meanwhile said the failure to arrest Mr Bashir had violated the country's constitution.
However, Sudan described the attempt to arrest Mr Bashir as "lame and meaningless".
Foreign Minister Ibrahim Ghandour told reporters at Khartoum airport that the court order was an attack on Sudanese sovereignty.
Mr Bashir arrived at the airport on Monday evening, dressed in white robes and waving a cane. He was greeted by cheering supporters.
The Sudanese leader is accused of committing war crimes, crimes against humanity and genocide during the Darfur conflict.
The UN says that about 300,000 people in Sudan have died since fighting began in 2003. More than 1.4 million people are thought to have fled their homes.
Government forces and allied Arab militias are accused of targeting black African civilians in the fight against rebels.
It is unlikely that South Africa will face sanctions for allowing Mr Bashir to leave the country even after a court order barred him from doing so, says the BBC's Nomsa Maseko in Pretoria.
A number of African countries have in the past decided not to co-operate with the ICC. The court has been accused of racism and bias against African leaders.
So as things stand, Mr Bashir appears to have left South Africa with the blessing of the African Union, our correspondent says.
On Monday, UN Secretary-General Ban Ki-moon said the ICC's warrant for the arrest of Mr Bashir must be implemented by countries who have signed up to the court's statutes.
As a member of the ICC, South Africa is obliged to arrest anyone charged by the court.
Press review: 'A precedent for other leaders'
The South African press has been considering the repercussions of the attempt to arrest Sudanese President Omar al-Bashir, who had been attending an AU summit.
IOL News said Mr Bashir's departure would leave "a major constitutional and diplomatic crisis and a big question mark over South Africa's continued membership of the ICC".
The Cape Times said the decision to invite the Sudanese president, despite his indictment by the ICC, had "exposed the fact that the AU considers the ICC largely irrelevant".
"This has the potential to sound the death knell of the ICC," the newspaper said, adding that the arrest "would set a precedent for other leaders on the continent who could be subject to the criminal jurisdiction of the ICC for their actions".
Before the summit, the ICC issued a press statement urging the South African government "to spare no effort in ensuring the execution of the arrest warrant".
Kenneth Roth, the director of advocacy group Human Rights Watch, tweeted that South Africa appeared to have "shamefully flouted" the ICC and domestic court to free a man "wanted for mass murder of Africans".
Darfur conflict: Key points
- Fighting began in 2003 when black African rebels in Darfur took up arms, accusing the government of neglect
- Pro-government Arab militias, known as Janjaweed, accused of responding with ethnic cleansing
- In 2008, the UN estimated that 300,000 people had died because of the war, though Khartoum disputes the figure
- More than 1.4 million people have fled their homes
- In 2010, the ICC charged President Bashir with genocide in relation to the Darfur conflict
- There have been several peace processes, but fighting continues, with numerous armed groups now active