8 suspects killed in clash with Mexican soldiers

The department cited an internal army report saying the clash occurred near the rural town of Madera, about 145 miles (230 kilometers) south of the U.S. border.

The gunmen apparently opened fire on an army patrol, but the Defense Department did not offer any information on the attack or the identity of the attackers. The area is frequently used by gangs to produce and traffic drugs.

Also Thursday, the U.S. Treasury Department added two companies owned by daughters of drug lord Ismael "El Mayo" Zambada to the list of sanctioned companies under the Narcotics Kingpin Designation Act.

In a press statement, the U.S. Embassy in Mexico City said the two women, Maria Teresa Zambada Niebla and Midiam Patricia Zambada Niebla, served as "front persons" for their father's illicit transactions. The companies named to the list are Arte y Diseno de Culiacan SA de CV and Autotransportes JYM SA de CV.

Any assets the businesses may have under U.S. jurisdiction are now frozen and U.S. citizens are barred from any financial or commercial dealings with them.

Zambada is wanted on drug trafficking charges issued by at least three U.S. district courts. His daughters had been identified by the Treasury Department as participants in his gang's operations since 2007.

Also Thursday, the army command in the border state of Tamaulipas said soldiers seized two extended pickup trucks painted with Mexican army emblems and colors near the border community of Ciudad Mier.