ANKARA, Turkey -- A man questioned over the disappearance of a New York City woman in Istanbul has been released from police custody but may be called again to help authorities with their inquiries, a Turkish news report said Friday.

Sarai Sierra, a 33-year-old mother of two, went missing while vacationing alone in Istanbul. She was last heard from on Jan. 21, the day she was due back home.

A police official in Istanbul said police had questioned a man who had been in contact with Sierra during her stay in in the city. The private Dogan news agency, quoting unnamed Turkish authorities, said the man was later released by a prosecutor. It has described the man as Turkish.

Sierra had arranged to meet her contact on a bridge she planned to photograph on the day she went missing, Turkish news reports said. Dogan said the meeting never took place.

Police officials in Istanbul weren't immediately available for comment.

Sierra left for Istanbul on Jan. 7 to explore her photography hobby and made a side trip to Amsterdam, Netherlands, and Munich, Germany. Her family last heard from her on Jan. 21, when she was supposed to start her journey home, but she never checked into her flight.

Sierra's husband, Steven, and brother, David Jimenez, travelled to Istanbul to help in the search. Sierra's children are 9 and 11.

Sierra had planned to go on the trip with a friend, but went alone when the friend couldn't make it.