This is from the US State Department's Website. It is an official warning for any American's visiting or living in Turkey.
==================================================
March 31, 2006
This Public Announcement is issued to alert Americans to ongoing security concerns in Turkey. Violent clashes involving security forces and sympathizers of the PKK terrorist organization are ongoing in the town of Diyarbakir in southeastern Turkey and in surrounding areas including Batman, Sirnak, and Sanliurfa. The main tourist areas of Ankara, Istanbul, Izmir, and the coastal regions currently are not affected by these clashes, but the unrest has the potential to spread to these regions as well. This Public Announcement expires on April 30, 2006.
Recent violent clashes leading to several deaths, many injuries, and the destruction of property have occurred in Diyarbakir, an area frequented by travelers to and from the Turkey/Iraq border. Roads to the airport have been closed periodically in the last several days and many businesses and schools are closed. Police and military forces have responded to large crowds of people by using tear gas, high-pressure water, and firearms. Tanks and other heavily armored vehicles have been brought into the area in response to the violence.
The Department of State advises U.S. citizens traveling or residing in Turkey to avoid these areas and to be alert for the high potential for violence when traveling in any of the southeast provinces. Department of State personnel are subject to travel restrictions in Sirnak, Diyarbakir, Van, Siirt, Mus, Mardin, Batman, Bingol, Tunceli, Hakkari, Bitlis, and Elazig provinces. Travelers who normally use the airport in Diyarbakir on their way into or out of Iraq should instead consider using Mardin airport near Turkey’s border with Syria.
The Department of State advises U.S. citizens traveling or residing in Turkey to avoid areas where crowds are expected to gather, to exercise caution, and to closely follow media reports. Even demonstrations intended to be peaceful can turn confrontational and possibly escalate into violence.
U.S. citizens living or traveling in Turkey are encouraged to register with the Embassy or nearest consulate through the State Department's travel registration website,
https://travelregistration.state.gov , and to obtain updated information on travel and security within Turkey. U.S. citizens without Internet access may register at the Consular Section of the U.S. Embassy in Ankara, at the Consulate General in Istanbul, at the Consulate in Adana, or with the Consular Agent in Izmir to obtain updated information on travel and security in Turkey. Embassy communications with the resident American citizen community, or “Warden Messages,” can be found on the Embassy’s website at
http://ankara.usembassy.gov .
For the latest security information, Americans living and traveling abroad should regularly monitor the Department’s Bureau of Consular Affairs Internet web site at
http://travel.state.gov , where the current Worldwide Cautions, Public Announcements, and Travel Warnings can be found. Travelers should also consult the Department of State’s latest Consular information Sheet for Turkey. Up-to-date information on security can also be obtained by calling 1-888-407-4747 toll free in the U.S., or, for callers outside the U.S. and Canada, a regular toll line at 1-202-501-4444. These numbers are available from 8:00 a.m. to 8:00 p.m. Eastern Time, Monday through Friday (except U.S. federal holidays).