ANKARA, Turkey (CBSNewYork/AP) — A special Turkish police task force looking for a missing Staten Island woman was sifting through “thousands of hours” of video recovered from about 500 security cameras in downtown Istanbul, Turkey’s state-run agency reported Thursday.

Sarai Sierra, a 33-year old mother of two, who was vacationing alone in Istanbul, has been missing since Jan. 21, when she was due to board her flight back home.

A police official told The Associated Press that police were still trying to locate a man who had exchanged online messages with Sierra in Istanbul.

Turkish news reports say Sierra had made arrangements to meet the man on a bridge she planned to take photographs of, on the day she disappeared, but it was not known if the meeting had taken place.

The state-run Anadolu said 28 police officers were assigned to scan security camera images from around the Taksim neighborhood, where she stayed in a hostel and around the nearby Galata Bridge she planned to visit.

Sierra left for Istanbul on Jan. 7 to explore her photography hobby and made a side trip to Amsterdam, Netherlands, and Munich, Germany.

Sarai Sierra Surveillance Image (credit: Handout)

Sarai Sierra Surveillance Image (credit: Handout)

Before she went missing, Sierra had been in regular contact with her family and friends and told relatives she planned to take photographs at the Galata Bridge.

Anadolu said Turkish authorities had also requested information from Germany and the Netherlands on her trips there. They were also seeking information from the U.S. about her bank account activities and mobile phone calls, it said.

On Thursday, a Turkish missing persons association joined the search, handing out flyers with photos of Sierra and urging anyone with information to call police. The group was driving a bus covered in posters of her through areas she had gone to, including Galata Bridge.

Sierra’s husband, Steven, and brother, David Jimemez, travelled to Istanbul to help in the search.

In New York, Sierra’s sister told the AP that Steven Sierra and Jimenez were “still getting information” on her disappearance.

“We’re just praying and hoping for her return,” Christina Jimenez said. “We love her and we thank everyone for their prayers that has supported us.”

Jimenez said she could not speak about the investigation.

Sierra had planned to go on the trip with a friend, but ended up going by herself when the friend couldn’t make it. Her belongings, including her passport, were found in her hostel room.

Police on Thursday released new security camera footage of Sierra going through security checks at Istanbul’s Ataturk Airport on her way to Amsterdam. She is seen alone, wearing jeans, a gray top and a gray hat.

The family said Sierra’s children, ages 11 and 9, do not know their mother is missing.

Staten Island Rep. Michael Grimm said his office is assisting in the case.

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