ANKARA, Turkey — Turkish police on Wednesday were trying to trace a person who apparently corresponded with a New York City woman through social networking sites before she went missing, an official said.

Sarai Sierra, a 33-year-old mother of two, has been missing since Jan. 21 when she was supposed to return home from a solo vacation in Istanbul. Police there have set up a special unit to find her.

A senior police official told The Associated Press that Sierra had exchanged messages with a person before she disappeared and police were now trying to trace the man or woman he described as a possible suspect in her disappearance.

The police official said Sierra "presumably met" the person after she arrived in Istanbul. He spoke on condition of anonymity in line with government rules that bar civil servants from speaking to journalists without prior authorization.

Turkey's private Dogan news agency, citing unnamed sources, said Sierra had exchanged messages through her email account with a person who went by the name of "Taylan" although it was not known if that was his real name or an alias.

It claimed the two agreed to meet on Galata Bridge, a tourist destination about 2 kilometers (more than a mile) from her hostel.

Dogan said police were scanning through security camera images around the bridge to see if the alleged meeting ever took place.

The agency said police had identified the IP address of the device "Taylan" had allegedly used to correspond with Sierra.