Found on Expedia:

24 January 1997=20

Taxi Assaults Pose Threat in Mexico City=20

WASHINGTON, D.C.  Americans visiting Mexico City should get into taxis=20
only at sitios, the authorized taxi stands which are found throughout the=
=20
city, the U.S. Department of State warns.=20
=A0=A0=A0=A0=A0Robberies, abductions, and assaults in taxis against travele=
rs and=20
U.S. Embassy employees have been increasing in frequency and violence,=20
according to a State Department public announcement.=20
=A0=A0=A0=A0=A0Travelers should avoid Volkswagen taxis and other cabs that =
cruise=20
                            ^^^^^^^^^^
the streets or wait for fares in front of restaurants, theaters, clubs,=20
and hotels. Instead, ask at your hotel for directions to a sitio, or call=
=20
authorized 24-hour taxi dispatch services in Mexico City at 271-9146,=20
271-9058, or 273-6125.=20