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Sudanese authorities have again detained a young mother a day after she was freed from death row where she'd been sent for refusing to renounce her Christian faith, FoxNews.com confirmed.

There were conflicting reports as to whether Meriam Ibrahim, who gave birth in a Khartoum prison after being sentenced to death in May for allegedly converting from Islam to Christianity, was arrested or just detained with her husband, Daniel Wani, at Khartoum airport as she tried to leave the country. Al-Sharif Ali, a member of her legal team, told FoxNews.com she was arrested in a show of force that included dozens of agents from the National Intelligence and Security Service.

"We don't have a reason as to why," said Ali. "Her husband is also being detained. We have tried to see them, but it has been very difficult. The national security force will not allow us to meet with them."

Ibrahim and Wani, as well as their two children, were taken to a facility used by Sudan’s National Intelligence and Security Service after the arrest, at 2 p.m. local time, a source close to the family told FoxNews.com. They had travel documents furnished by the U.S. embassy, but Ibrahim did not have a passport, the source said.

"She is either banned from traveling or the NISS could also create "papers issues" if they don't want her to leave the country," the source said.

Wani holds dual U.S.-Sudanese citizenship, and Ibrahim's supporters argued that their children, including a daughter named Maya born in prison in May and a 20-month-old boy named Martin who was imprisoned with her, are U.S. citizens.

The U.S. State Department disputed the claim Ibrahim was arrested and said Washington is working to secure her freedom.

“"The State Department has been informed by the Sudanese government that while the family was temporarily detained, they have not been arrested and the government has assured us of their safety," said spokeswoman Marie Harf. "The Embassy has been and will remain highly involved in working with the family and the government.

"The State Department is engaging directly with Sudanese officials to secure their safe and swift departure from Sudan," Harf added.

Supporters of Ibrahim say they won't feel she is safe until she is out of the war-torn nation.

"We're encouraged that the State Department is engaged and working to secure the freedom of Meriam and her family," said Jordan Sekulow, executive director of the American Center for Law and Justice, which gathered more than 300,000 signatures for an online petition demanding Ibrahim's freedom. "Whether Meriam and her family have been 'temporarily detained' or arrested, holding U.S. citizens against their will is extremely disturbing and unacceptable. It has always been our concern that the only way the Ibrahim family could be truly safe is to leave Sudan."

Ibrahim, 27, refused to renounce her Christian faith in court in May, prompting a judge to sentence her to hang for apostasy. The case became an international cause, with several U.S. lawmakers and the State Department blasting the decision as barbaric. Sudan's national news service SUNA said the Court of Cassation in Khartoum on Monday canceled the death sentence after defense lawyers presented their case, and that the court ordered her release.

Sources close to the situation told FoxNews.com on Monday that Ibrahim's lawyers were scheduled to meet with representatives from the U.S. Embassy on Tuesday. Ali told FoxNews.com he is still hoping to reach a resolution, and plans to try to see Ibrahim on Wednesday.

Ibrahim and Wani were married in a formal ceremony in 2011 and operate several businesses, including a farm, south of Khartoum, the country’s capital.

Wani fled to the United States as a child to escape the civil war in southern Sudan, but later returned. He is not permitted to have custody of his son because the boy is considered Muslim and cannot be raised by a Christian man.

Ibrahim’s case first came to the attention of authorities in August, after members of her father’s family complained that she was born a Muslim but married a Christian man. The relatives claimed her birth name was “Afdal” before she changed it to Meriam and produced a document that indicated she was given a Muslim name at birth. Her attorney has alleged the document was a fake.

Ibrahim says her mother was an Ethiopian Christian and her father a Muslim who abandoned the family when she was a child. Ibrahim was initially charged with having illegitimate sex last year, but she remained free pending trial. She was later charged with apostasy and jailed in February after she declared in court that Christianity was the only religion she knew.

“I was never a Muslim,” she told the Sudanese high court. “I was raised a Christian from the start.”

Sudan’s penal code criminalizes the conversion of Muslims to other religions, which is punishable by death. Muslim women in Sudan are further prohibited from marrying non-Muslims, although Muslim men are permitted to marry outside their faith. Children, by law, must follow their father’s religion.