An American citizen arrived safely in Oman on Wednesday after more than six years in detention in Iran, but one of his sons remains imprisoned in Tehran, his family said.
Baquer Namazi, 85, flew to Oman's capital, Muscat, from Iran and is due to travel on to the United Arab Emirates, where he will undergo urgent surgery to clear a "severe blockage" of an artery, his family and lawyer said in a statement.
His son Siamak Namazi, 51, was granted a one-week furlough for the first time in seven years of imprisonment before his father flew out of the country.
"It is impossible to articulate and describe sufficiently how I am feeling. I am just so grateful that after so long, I will shortly be able to embrace my father again," Babak Namazi, Baquer Namazi's son and the brother of Siamak Namazi, said in a statement.
But it was a "bittersweet" day because his brother and two other American citizens remain imprisoned, Namazi said.
"My brother Siamak as well as Americans Emad Sharghi and Morad Tahbaz remain detained in Iran and our nightmare will not be over until our entire family and the other Americans are reunited with their families," he said.
Namazi expressed gratitude to Oman for its role in enabling his father's trip out of Iran, the United Arab Emirates for hosting his father for medical treatment in Abu Dhabi, the U.N. secretary-general for working to get his father released, and the governments of Switzerland, the United Kingdom, Qatar and the U.S., "which has worked on my family's cases for years."
He also thanked current and former employees of UNICEF, who he said supported his family, and human rights groups and journalists, who "all helped me keep public attention on my family's plight."
Baquer Namazi, who had worked as a senior official for UNICEF before he retired, was arrested in February 2016 when he traveled to Iran to appeal for the release of his son Siamak, a businessman, who had been arrested in 2015.
Iranian authorities charged both men with espionage, but human rights advocates, the United Nations and the U.S. government have said that the charges were without foundation and that the men were unlawfully detained.
Baquer Namazi was placed on medical furlough in 2018, and eventually his case was declared settled, but he had faced a travel ban and could not leave the country.
The Biden administration on Tuesday denied a report by Iranian state media that the U.S. would release billions of dollars to Iran that U.S. sanctions have blocked in South Korea now that Baquer Namazi had been allowed to leave the country.
"We understand the lifting of his travel ban and Siamak's furlough were related to medical need. They were not part of any deal or anything like that," State Department deputy spokesperson Vedant Patel told reporters, adding that reports to the contrary were "absolutely false."
This article was originally published on NBCNews.com