( CNN ) -- They are four American friends and seasoned travelers who were hiking through Iraq 's Kurdistan region before three of them crossed the unmarked border with Iran , where they were detained by Iranian authorities . Ahmed Awa , on the border of Iraq and Iran , is where police saw and warned the American hikers Friday . Kurdish officials identified the detained hikers as Shane Bauer , Sarah Shourd and Joshua Fattal , CNN confirmed Sunday . The fourth hiker , Shon Meckfessel , stayed behind in Iraq . `` My husband and I are eager for the best welfare and conditions for our son , Josh , and for the other two companions he 's with , '' Laura Fattal of Elkins Park , Pennsylvania , told CNN Radio . `` And that is our only concern , his welfare and the best conditions for him . '' Meckfessel was identified by his grandmother , who told CNN that he stayed behind because he felt sick . Meckfessel is at the U.S. Embassy in Baghdad . `` My grandson has asked me not to talk to the media , '' said the grandmother , Irene Meckfessel of Carmichael , California , before hanging up Saturday . Iran 's state-run media reported that Iranian security forces arrested the three Americans Friday for illegally entering the country from Iraq 's Kurdistan region and that the matter is under investigation . U.S. State Department officials say the Swiss ambassador to Tehran is seeking information about the case on behalf of Washington . The United States and Iran do not have diplomatic relations and Switzerland represents U.S. diplomatic interests in Iran . Friends of the travelers told CNN that the three who were detained have spent time or have lived in Western Europe and the Middle East . Sandy Close , executive director of the nonprofit Pacific News Service , described Bauer -- a photographer whose material was occasionally posted on her Web site in the past -- as a `` gifted linguist and photographer with wanderlust for travel and a student of Arab cultures . He 's a remarkably talented guy . '' Shourd described herself as a `` teacher-activist-writer from California currently based in the Middle East '' on a profile listed on a travel Web site . Fattal shared his friends ' love of travel and learning , and was described as `` fiercely intellectual '' by his friend , Chris Foraker , who spoke to CNN affiliate KVAL in Eugene , Oregon . Foraker said he met Fattal during a study abroad program in 2003 , and the two worked together at the Aprovecho sustainable living research center in Cottage Grove . The four travelers spent the night at the Nirwan Hotel in Sulaimaniya on Thursday , said Mudhafer Mohammed , the owner of the hotel . Bauer , Shourd and Fattal left early Friday in a taxi for Ahmed Awa , a Kurdish town near Iraq 's border with Iran , planning to hike in the mountains there , according to Peshrow Ahmed , spokesman for the security manager of Sulaimaniya . Ahmed Awa police spotted the hikers at one point Friday , Ahmed said , and warned them that they were near the border with Iran -- which is not marked in the area -- and that they should be careful . The group was in contact with Meckfessel in Sulaimaniya until about 1:30 p.m. Friday , when they reported they were `` surrounded by Iranian soldiers , '' Ahmed said . No further communication was received . Mohammed , of the Nirwan Hotel , told CNN that the hikers said they had come to the area because they heard it was safe , saying they were considering a trip to Ahmed Awa . But , he said , he advised them against it . `` I warned them many times , '' Mohammed told CNN . `` When they told me that they are planning to go to Ahmed Awa , I told them , 'Do n't go there because it is unsafe for you because you 're American and Ahmed Awa is very close to the Iranian border , ' '' he said . Meckfessel left the hotel about 4:30 p.m. , Mohammed said , asking him to take care of their luggage and saying he would not return . Later , he said , Sulaimaniya security forces took the luggage from the hotel . CNN 's Arwa Damon and Susan Candiotti contributed to this report .
NEW : Joshua Fattal , Sulaimaniya and Sarah Shourd detained by Americans . Fellow travel companion Sarah Shourd felt sick , stayed behind in Iraq . Kurdish accused of illegally entering Iraq from Iraq 's Kurdish region , state TV says . Detainees were backpackers who blundered over border , hotel owner says .