MANAGUA, Nicaragua (CNN) -- An American man held in a Nicaraguan jail was released Friday and left the country, four days after a court overturned his conviction on charges of murdering his former girlfriend.
Magazine publisher Eric Volz had been sentenced to 30 years.
But Eric Volz "will be in hiding, due to reports of threats against him," his family said in a statement.
"We have reason to believe he is being followed and are taking every precaution to assure his safety."
Volz's family also expressed both enormous relief and worry after his release.
"We are so thankful, so thankful for this gift," his mother said upon arriving in Atlanta, Georgia, from Nicaragua on Friday night. Watch Volz's mother describe her feelings »
But Volz is very sick, Maggie Anthony added.
"We're really concerned for his health. And mentally and physically, this past week has been ... just [an] incredible strain on him, on his mind and body," she said.
Volz has kidney stones, according to a family spokeswoman.
After stopping in Atlanta, Anthony traveled to Nashville, Tennessee, where she said she would worry about her son "until he's on U.S. soil." She would not say where he was.
A mix-up kept Volz, 28, of Nashville, in custody in Nicaragua after an appeals court reversed the ruling that found him guilty of the 2005 death of Doris Jimenez.
Thursday night, a Nicaraguan appeals court in Granada cleared up the confusion and signed release papers for Volz, said Maria Jose Oviedo, assistant to one of the judges on the court.
Once the documents were processed by the police hospital in Managua -- where Volz was undergoing treatment for a variety of ailments -- he was set free under Nicaraguan law.
Volz left Nicaragua on Friday afternoon, said Eddie Vasquez, a spokesman for the U.S. State Department.
The United States "has been working this a lot, at just about every level possible, to make sure the court decision was implemented," a senior State Department official told CNN.
The U.S. ambassador to Nicaragua has spoken to officials up to and including President Daniel Ortega in order to push the case along, the official said.
"We were pretty confident the court decision would be implemented, simply because the decision to overturn the case was significant, and from our point of view, it would have not been in the interests of the Ortega government not to implement it," the official said.
But media attention increased the challenge facing the Nicaraguan government, because it needed to be seen as implementing the decision instead of caving to international pressure, the official said.
Volz's release came despite prosecutors' decision to appeal the case to the Supreme Court. Magistrate judges in the appeals court in Nicaragua have up to 10 days to review the request for appeal. Watch how Volz was convicted »
The delay began after the Managua judge who sentenced Volz to 30 years in prison stalled over court documents, Volz's attorney said.
Attorney Fabbrith Gomez said the judge, Ivette Toruno Blanco, claimed that the documents were incorrectly numbered and that she had returned them to Granada.
Magistrates in Granada spent the rest of the week trying to find Volz's case file. Once the files were found, the appeals court judges "stayed up late" Thursday night working on the paperwork for release, Oviedo said.
The order was delivered to the hospital in Managua, Nicaragua's capital, about 30 miles from the city of Granada, on Friday.
"You know, it hasn't hit me yet," Volz's mother said later.
"We have been living on the edge for over a year now, and I just haven't had time to digest yet."
Anthony said she's grateful for the encouragement her family received.
"People writing e-mails, donating money, we're just so appreciative of everybody's support, and we just can't thank people enough for it."
The family just wants to heal, she said.
"Try to take some time to be quiet. Just try to put our arms around each other and just be a family again, is what we want to do. That's our biggest plan."
Volz was convicted in 2006 of raping and killing Jimenez.
Ten witnesses in the case testified or gave affidavits swearing that he was in his office in Managua, two hours away from the town where Jimenez was killed, at the time of her slaying. He founded and was publisher of EP (El Puente) magazine.
But one man testified that he had seen Volz in the town, San Juan del Sur, just after the time police believe Jimenez was killed.
That man, Nelson Danglas, was originally arrested in the slaying but received full immunity in exchange for his testimony against Volz. No physical evidence from the scene linked Volz to the slaying.
In addition to Volz, the same court convicted another man, Julio Chamorro, of the murder, although investigators never connected him with Volz.
Police said Jimenez was raped and strangled in the dress shop she owned in San Juan del Sur.
By the time the verdict against Volz was reached, a mob had gathered outside the courtroom chanting for his conviction. E-mail to a friend
CNN's Edmundo Garcia and Elise Labott contributed to this report.
Copyright 2007 CNN. All rights reserved.This material may not be published, broadcast, rewritten, or redistributed. Associated Press contributed to this report.
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