A British security consultant kidnapped six days ago by gunmen in Somalia has described his release as "marvellous", Save the Children says.
A worker for the charity, Zimbabwe-born Frans Barnard, and a local colleague, who was later freed unharmed, were seized in Adado last Thursday.
The charity said Somali clan elders had negotiated Mr Barnard's release and that he was safe and well.
It said no ransom had been paid to his kidnappers.
'Relatively safe area'
Mr Barnard had gone to the area to see if it was safe enough for Save the Children to set up a new base to help malnourished and sick children, along with their families.
But on the evening of 14 October, a group of masked gunmen stormed the building, used as a staff residence.
The kidnappers climbed in through a window and fled with their hostages into an area said to be controlled by the hardline Islamist group al-Shabab, which has links to al-Qaeda.
After he was released, a very relieved Mr Barnard spoke to the BBC.
"I'm good. I'm happy to be not where I was. It's fair to say absolutely no-one expected any resolution quite this quickly," he said.
In a statement released by the charity, Save the Children's chief executive Justin Forsyth said: "We believe Frans was abducted by an independent group of criminals with no political affiliation or support from other groups in the region."
He added: "Save the Children's policy is not to pay ransoms and we did not pay a ransom to secure Frans' release."
He said the release had been negotiated by clan elders in Somalia and the charity was grateful to those involved in securing his release.
He earlier told BBC Radio 4's Today programme the kidnappers had looked after Mr Barnard and the local community had offered to help as they had "felt it was wrong that he had been kidnapped".
Anna Ford, a Save the Children spokeswoman, said: "We spoke to him and he said 'it is bloody marvellous' - he confirmed that he was safe and well and was confident in the people who were looking after him."
She later said that Mr Barnard was now back in Adado and added: "He has had a shower, he has had a good meal, and he is being looked after by the local president.
"Our main objective now is to reunite him with his family as soon as possible."
David Cameron told the House of Commons during prime minister's question time that he was delighted Mr Barnard had been released.
He said: "We have been in close contact with Save the Children over the kidnap of Frans Barnard who was doing vitally important work on their behalf in Somalia.
"Let me praise the professionalism of Save the Children and also thank the Somali clan members who were involved in his release. I'm sure that it will be good for him to be back with his family after what must have been a very difficult and frightening few days."
The BBC's East Africa correspondent Will Ross said Mr Barnard was freed before dawn on Wednesday after intervention from local officials.
He said the head of the local administration had negotiated the release after driving with armed guards for several hours to reach the armed hostage takers.
Mr Forsyth said the charity would remain committed to its work in Somalia helping vulnerable children.
Adado, which is near the Ethiopian border, is also closely linked to pirate groups who routinely take ships and crew hostage.
Until now, Adado had been seen as a relatively stable part of Somalia, with aid groups considering relocating there after being forced out of more volatile regions.
Several foreigners have been kidnapped in Somalia in recent years. Most have been freed unhurt.