Iran has arrested three Americans who strayed across the border from Iraq on allegations they illegally entered the country, and a lawmaker said Tuesday that authorities are deciding whether they will be accused of spying. Officials in northern Iraq's Kurdish region said Sunday that the three - Shane Bauer, Sarah Shourd and Joshua Fattal - were tourists who inadvertently crossed into Iran on July 31 while hiking in the region. Friends and family say the three were adventurous travelers who accidentally stumbled into the wrong place at the wrong time. Their arrest and Iran's accusations could spark a new standoff with the United States at a time when Iran is already mired in its worst political crisis in decades over the disputed June 12 presidential election. Earlier this year, the two countries faced off over American-Iranian journalist Roxana Saberi, who was held for more than three months and accused of spying. Lawmaker Mohammad Karim Abedi, who heads the Iranian parliament's National Security Committee, said on state-run Arabic television Al-Alam that he believed the three came as spies but authorities are still deciding whether there is proof to bring legal action against them. "Surely we can say that they came as spies," he said. "The concerned authorities will decide whether they were spies or not," he added. "If it is proven that they were spies, the necessary legal procedures will be sought against them." The US State Department's deputy spokesman, Robert A. Wood, dismissed the insinuations of espionage. "I don't think these reports are credible at all," he said. Wood said the Swiss ambassador has met with Iranian officials on Washington's behalf but did not get confirmation the three had been detained. Wood said the United States was still trying to find out. "The Swiss ambassador's trying to ascertain the information and location of these individuals but hasn't been able to do so," Wood said. "But he's going to continue push to try to get that information for us." Switzerland represents US interests in Iran because the two countries do not have diplomatic relations. Earlier in the day, the hard-line Fars news agency, considered close to Iran's elite Revolutionary Guard, quoted the deputy governor of Iranian Kurdistan province near the Iraqi border as saying the three illegally entered Iran and were arrested. "The three, who are not identified yet, were detained at the Malakh-Khor border point near the town of Marivan," about 370 miles (630 kilometers) west of the capital Teheran, Fars quoted Iraj Hassanzadeh as saying. "Two of the three are men. They were not interrogated," he said, adding that anyone who crossed the border illegally would be arrested. He said the Americans had Iraqi and Syria visas. Saberi's case put new strains on the already rocky US-Iran relationship at a time when President Barack Obama sought to reach out to Teheran for a dialogue over its contentious nuclear program. Saberi was arrested in January and accused of spying. The US denied the charges, but she was sentenced to eight years in prison. An appeals court reduced that to a two-year suspended sentence and released her on May 11. One of the Americans detained this time, Bauer, is also a journalist, according to his Web site. The freelance reporter and photographer is based in the Middle East and has reported from Iraq, Syria, Sudan's Darfur region and Yemen, his Web site says. He was in the region to cover the July 25 regional elections in Iraq's self-ruled Kurdish area. Family members identified Fattal as another one of the detained. His father, Jacob, told The Associated Press on Monday that he did not have any updates from the State Department about his son, who graduated from the same university as Bauer. US Secretary of State Hillary Rodham Clinton appealed Monday to Iran for information on the three Americans to help determine their whereabouts. Swiss diplomats have been trying to obtain details from Iran on behalf of the Americans. Switzerland represents US interests in Iran because the two countries do not have diplomatic relations. In the US, Pacific News Service Executive Director Sandy Close, who hired Bauer to cover the elections in Kurdistan, said she does not believe the freelance journalist ever intended to go to neighboring Iran. In an e-mail, Bauer told Close he wanted to "feel out the situation (in Kurdistan) and get some ideas for deeper stories." "Kurdistan is the big story in Iraq now," Bauer wrote in the e-mail provided to The Associated Press. "I'm off to Kurdistan ... " Close said Bauer went backpacking with Shourd, his girlfriend, in a popular tourist area renowned for its scenery. It was unclear how the two met up with Fattal. A fourth member of the group, Shon Meckfessel, was to have gone on the hike but did not because he felt sick. Close said Bauer would not have deliberately tried to enter Iran. "He did not express any interest in going to Iran. He did not speak Farsi, his passion was Arabic," she said. Bauer has traveled to the Middle East and North Africa and was most recently based in Damascus where he is working on a film about Darfur. Bauer's mother, Cindy Hickey of Pine City, Minn., and Shourd's mother, Nora Shourd, said they are concerned for the safety and welfare of the group and hope they return safely. Fattal's father Jacob, who runs a tech magazine outside Philadelphia, also told reporters: "All we care about is the well-being of Josh and his two hiker friends." A Kurdish official in Iraq has said the three contacted a colleague to say they had entered Iran by mistake on Friday and were surrounded by troops. Iran's state television initially said only that the Americans were arrested after they did not heed warnings from Iranian border guards. Bauer and Shourd, both graduates of the University of California, Berkeley, had been living in the San Francisco Bay area. Close described Bauer as "an artist whose first love is photography. He's also linguistically gifted and just wanted to immerse himself in the Middle East." Shourd has written for a number of online publications, including Brave New Traveler. She has also has taught English. Ross Borden, founder of an online travel magazine that includes Brave New Traveler, described Shourd as "very professional. She wrote a great story for us." "She's obviously a professional traveler, as you can see by her latest adventure, going hiking in Iraq," he said. "Not many people go hiking in Iraq." Fattal spent three years recently living with a group dedicated to sustainable farming near Cottage Grove, Ore. He lived with about nine others and worked as the group's intern coordinator before leaving about eight months ago, according to Jason Brown, who now holds Fattal's job. From January to June, Fattal traveled overseas as a teaching assistant with the International Honors Program, visiting Switzerland, India, South Africa and China on a global ecology program. Fattal had been a student in the program during college, president Joan Tiffany said. "He's a very thoughtful, caring person, soft-spoken, smart, bright. Has lots of travel experience, and is someone that I would expect to be an experienced camper," Tiffany said.