Germany heaved a sigh of relief following news of the release of Susanne Osthoff, a 43-year-old German archaeologist and aid worker, in Iraq after more than three weeks in captivity.

Osthoff's sister Anja last week complained over a lack of public support for her sister, whose plight initially failed to ignite the same emotional response among Germans as was seen in countries like France and Italy which have also had nationals taken hostage in Iraq.

But as the saga continued, public support for Osthoff has grown and her release was greeted with joy on Sunday.

"It is the best news of the Christmas season. She is alive, she is free, she is in good health," the tabloid Bild newspaper said.

Deputy government spokesman Thomas Steg said Chancellor Angela Merkel was "very relieved that this hostage drama came to a happy ending."

Driver's whereabouts unclear

Reports said that Osthoff wasn't planning to come to Germany right away.

"Osthoff wishes to spend several days with her daughter but she has indicated that she will leave Iraq in the near future," foreign ministry spokesman Martin Jäger told a press conference Monday.

Osthoff has a 12-year-old daughter from a failed marriage to an Iraqi. She had been doing aid work in Iraq for several years.Osthoff hails from Glonn in the southern German state of Bavaria where Osthoff's daughter also lives. It was not clear where the mother and child would be reunited.

Jäger said the German authorities have been assured that her Iraqi driver Shalid al-Shimani had also been freed following Osthoff's release on Sunday, in sound health, after 24 days in the hands of unknown kidnappers.

The pair was seized on November 25 in the Nineveh region of northwest Iraq.

But while Osthoff was "at the moment still at the German embassy in Baghdad," Shimani's whereabouts were unknown, Jäger told journalists. "We were told that he is free but as yet he has not come to the German embassy," Jäger said.

Details wrapped in secrecy

Jäger added that "the German government and the German embassy in Baghdad were involved" in securing Osthoff's release, but he declined to give further details, including whether the United States had helped.

Indeed, mystery still surrounds the German government's exact role in freeing Osthoff. Questions such as who exactly played mediator and whether any ransom was paid still remain unanswered on Monday -- and are likely to remain under wraps.

Gernot Erler, Germany's deputy foreign minister said Monday that leaking the details of Osthoff's release to the public would give potential kidnappers indications of "how to handle something like this and how they could achieve results with what means and resources."

Given that at least five further Westerners are still being held by kidnappers in Iraq, experts have also indicated that going public with the details of Osthoff's release could hamper ongoing efforts towards freeing them.

Security experts say Germany has paid ransoms for hostages in the past and would probably have done so for Osthoff as well.

Two years ago, the German government managed to secure the release of 14 German hostages in the Sahara desert after they were held for six months in captivitiy. At the time, then German Foreign Minister Joschka Fischer said negotiations had been "extremely difficult," prompting the media to speculate that Berlin had paid some five million euros as ransom to the kidnappers. However, the reports were never confirmed.

Speculation continues

German newspapers on Monday noted that most of the ircumstances surrounding the kidnapping remained a mystery, while the government said Osthoff had decided not to talk about the experience.

"Osthoff has made it clear that she does not wish to speak about the circumstances of her kidnapping," Jäger said.

She was the first German national to be taken hostage in Iraq, and the kidnapping posed the first serious crisis for Merkel since she took office last month.

The daily Berliner Zeitung said on Monday that Merkel's government had "acquitted itself well in its first foreign policy crisis. The chancellor and her foreign minister acted with discretion," it said.

But speculation over whether the government had paid a ransom continued unabated.

"Even after her release the affair remains mysterious," Bild said.

Merkel had appealed to the kidnappers to release the pair, but insisted that Berlin would not be blackmailed.

The weekly magazine Focus said that according to foreign ministry sources, Osthoff was seized by a group calling itself the Army of the Mujahedin, which initially thought she was a spy working for a Western government, but later realized she was not.

According to German press reports in November, the kidnappers set an ultimatum of a few days for Germany to change its policy towards Baghdad as the price for Osthoff's release shortly after she was seized.

Berlin has refused to send troops to Iraq but has been helping to train Iraqi policemen -- though not on German soil.