A recent UC Berkeley graduate on a trip to learn more about the Middle East is among a group of Americans being held in Iran.
The United States is using Swiss diplomats to try to learn more about the status of the three, who were seized by Iranian guards on Friday.
Kurdish officials confirm their identities as Shane Bauer, Sarah Shourd and Josh Fattal.
The trio was hiking in the mountains in Northern Iraq when they reportedly crossed the border into Iran.
Tehran-based television news channel al-Alam quoted an Iraqi police officer as saying the trio were “working with the CIA.”
Bauer graduated with honors from UC Berkeley in 2007 with a degree in Arabic and peace and conflict studies. He is a freelance journalist whose work has appeared in numerous publications including the San Francisco Chronicle, L.A. Times, The Nation, Slate.com and San Francisco Bay Guardian.
Bauer's mother, Cindy Hickey, told the Associated Press Monday that she was concerned about her son and the other two who were detained.
"Our family is concerned about the safety and welfare" of the three, Hickey told the AP. She refused to comment further.
The three contacted a colleague Friday to say they had entered Iran by mistake and were surrounded by troops, according to a Kurdish official. According to Iranian media reports, Bauer and two others were arrested after they refused to heed warnings from border guards while hiking in the mountains in Kurdistan.
In Washington, Secretary of State Hillary Rodham Clinton appealed to Iran for information on the three Americans and called on Tehran to help the United States determine their whereabouts.
Bauer's Web site describes him as a fluent Arabic speaker and his Facebook page says he is in a relationship with Sarah Shroud.
Shroud, the only woman in the group, is also an aspiring journalist. Her Web site says she is a teacher, writer and activist living in the Middle East. Sandy Close, executive director of Pacific News Service where Bauer used to work, said one of Bauer's good friends told her Saturday that Shourd was taken into custody with Bauer, but she had no other details.
Fattal said he was also looking forward to traveling to Iraq and Kurdistan. Apparently of Arab origin, Fattal said in his last posting on Facebook Wednesday that he was getting in touch with his roots between the Tigris and Euphrates valleys.
Fattal's mother in Elkins Park, Pennsylvania issued a statement Sunday, saying "my husband and I are only concerned with the health and welfare of Josh, Shane and Sarah."
The U.S. State Department said, "We have been in touch with and are assisting the family members of the missing three Americans."
A fourth American, also from Northern California was traveling with the group but opted out of the hike because he had a cold.
Shon Meckfessel sat out because he had a cold, his grandmother, Irene Meckfessel, told The Associated Press from her home in Carmichael, Calif. He called her Saturday from the American Embassy in Baghdad, she said.
Sacramento TV station Fox 40 report Meckfessel is the bass guitarist for the Sacramento rock band Cake.
Switzerland has represented U.S. interests in Iran since American diplomats were taken hostage at the embassy in Tehran 30 years ago.
"Obviously, we are concerned," Clinton said. "We want this matter brought to a resolution as soon as possible and we call on the Iranian government to help us determine the whereabouts of the three missing Americans and return them as quickly as possible."
State Department spokesman P.J. Crowley told reporters later that the Swiss ambassador in Tehran met with Iranian officials Sunday. The Iranians told the Swiss that they could not confirm the detention of the Americans, Crowley said.
Crowley said the fourth American who did not accompany the missing hikers has provided good information to U.S. officials in Baghdad. He did not elaborate.
"We have three Americans who are missing. We want to know what happened to them," Crowley said. "Clearly, we want them back as quickly as possible."
Iran's Al-Alam TV quoted Colonel Anwar Haj Omar of the Halabja police force in northern Iraq as saying the three Americans were “agents” employed by the CIA.