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Turkish authorities have identified a person of interest in the hunt for an American woman who mysteriously disappeared in Turkey, according to a New York lawmaker, who called on authorities in both nations to pull out all stops in the search.

Rep. Michael Grimm, R-N.Y., is urging U.S. and Turkish officials to bolster the investigation into the whereabouts of Sarai Sierra, a  33-year-old mother of two from Staten Island, N.Y. Sierra, a freelance photographer, traveled to Istanbul alone on Jan. 7 and failed to return on a flight Jan. 22.

On Wednesday, a Turkish official said police are trying to trace an individual whom Sierra allegedly corresponded with through social networking sites. A source familiar with the investigation told FoxNews.com that Sierra may have contacted an "amateur tour guide" online to show her around popular sites in the city.

Grimm told FoxNews.com that Turkish police have identified a person of interest who may have contacted Sierra a day before she went missing. It was not known if authorities have located the person.

"One good thing here is that Istanbul has a very good local police department," Grimm said. "They’ve interacted with our U.S. law enforcement at all levels. I have a great deal of confidence. They are taking it very seriously."

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Hürriyet Daily News, an English-language newspaper in Turkey, reported Wednesday that authorities are searching for four Turkish citizens who contacted Sierra while she was in Istanbul. The individuals include a man named "Taylan" who police say arranged to meet Sierra by the Galata Tower on Jan. 20, according to the paper's website. It was not clear if "Taylan" is the person of interest Grimm referred to.

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Sierra's husband, who is in Turkey assisting with the search, reportedly gave authorities access to his wife's Facebook and Twitter correspondence. The woman's family last had contact with her on Jan. 21.

After arriving in Turkey on Jan. 7, Sierra later boarded flights to at least two other countries -- Germany and the Netherlands -- before returning to Istanbul, according to family members. On Tuesday, Turkish investigators released surveillance video showing Sierra two days before she was scheduled to return to the U.S. The video shows the young woman eating alone in a food court and walking around a shopping mall not far from the hostel where she was staying. The website also reports that Sierra's travel expenses in the three countries totaled more than $10,000.

Grimm, who represents New York's 11th District, which includes Staten Island, is a former FBI agent. In a statement issued Saturday, he said he was "troubled" by the facts surrounding the case.

"We remain in constant contact with officials in the U.S. and Istanbul, and will continue to urge them to use all available resources to find Ms. Sierra," Grimm said. "I am committed to standing with her family every step of the way until she is back safe in Staten Island."

Grimm spoke Monday to the U.S. ambassador in Istanbul, the Turkish ambassador in the U.S. and the chief in Turkey for the State Department. All are coordinating a full scale investigation to locate Sierra and have engaged the highest levels officials on this case, according to Grimm's office. The FBI is also investigating.

"The human aspect of this is not lost," Grimm told FoxNews.com. "They are looking at this missing person as if she were one of their own -- a wife or daughter."

The woman's sister, Christina Jimenez, said the family is requesting privacy while authorities conduct their search.

"I spoke to my sister every day," Jimenez told FoxNews.com Wednesday. "I miss her so much and love her. That's all I can say."