The Swede, who was kidnapped at gunpoint as he left work in the provincial capital Zinjibar on Thursday to travel to the main southern city of Aden, was in good health after his ordeal, the official added.
“The Swede was freed after the kidnappers received assurances from the local government that President Ali Abdullah Saleh would personally review the case of one of their clansmen,” said the official, who works in Khanfar district where the hostage was taken.
A security official told AFP earlier that the kidnappers were believed to be members of the Maraqish tribe, which has been campaigning for the release of a clansman on death row in the capital Sanaa.
A spokesman for the Swedish foreign ministry in Stockholm said it had little information about the abduction.
“We have no confirmation he was even a Swede, though he seems to be,” spokesman Anders Jorle said.
Yemen’s powerful tribes often kidnap foreigners for use as bargaining chips in disputes with the central government. Of about 200 foreigners seized in Yemen over the past decade, almost all have been released unharmed.
After the brief abduction of two US tourists in May from near Hajara, a village west of the capital which is famed for its historic mountaintop buildings, Yemen pledged tough action against kidnappers of foreigners.
The security forces had been engaged since mid-2008 in a “relentless war against abductions and those responsible for them… the kidnappers being as dangerous as terrorists,” an interior ministry statement said at the time.
Yemen is the ancestral homeland of al-Qaeda leader Osama bin Laden and, with US military aid, the security forces have also been fighting a mounting campaign of attacks by the jihadist network’s local affiliate.
The formerly independent south has also seen a wave of protests in recent months by supporters of the Southern Movement, a coalition of groups campaigning for autonomy or secession.