Masked students confront federal police outside the Acapulco airport as they protest the disappearance, and probable murder, of 43 students in the state of Guerrero, Mexico, Monday, Nov. 10, 2014. Relatives and supporters battled federal police in Acapulco, then blocked roads leading to the Pacific resorts airport, forcing tourists to walk to the terminal. The 43 teachers-school students disappeared at the hands of a city police force on Sept. 26 in the town of Iguala. (AP Photo/Bernardino Hernandez)
The relatives of 43 missing students hold posters of their missing loved ones as they protest their disappearance, and probable murder, in the state of Guerrero, at the Acapulco airport in Mexico, Monday, Nov. 10, 2014. Supporters of the missing students, refusing to believe they are dead, have kept up the protests that have blocked major highways and set government buildings ablaze in recent weeks. The 43 teachers-school students disappeared at the hands of a city police force on Sept. 26 in the town of Iguala. (AP Photo/Marco Ugarte)
A demonstrator carries a pipe during a protest against the disappearance, and probable murder, of 43 students in the state of Guerrero, at the Acapulco airport in Mexico, Monday, Nov. 10, 2014. Supporters of the missing students, refusing to believe they are dead, have kept up the protests that have blocked major highways and set government buildings ablaze in recent weeks. The 43 teachers-school students disappeared at the hands of a city police force on Sept. 26 in the town of Iguala. (AP Photo/Marco Ugarte)
Travelers walk to their terminal due to students protesting the disappearance, and probable murder, of 43 students in the state of Guerrero, at the airport in Acapulco, Mexico, Monday, Nov. 10, 2014. Supporters of the missing students, refusing to believe they are dead, have kept up the protests that have blocked major highways and set government buildings ablaze in recent weeks. The travelers eventually left the airport, missing their flights. (AP Photo/Marco Ugarte)
Magnolia Seguino, who lives in New Jersey, waits with her luggage behind a line of masked students blocking access to the airport as they protest the disappearance, and probable murder, of 43 students in the state of Guerrero, in Acapulco, Mexico, Monday, Nov. 10, 2014. Supporters of the missing students, refusing to believe they are dead, have kept up the protests that have blocked major highways and set government buildings ablaze in recent weeks. Seguino eventually left the airport in a bus provided by her hotel. (AP Photo/Marco Ugarte)
Estudiantes bloquean el acceso al aeropuerto de Acapulco en protesta por la desaparición y probable muerte de 43 estudiantes del estado de Guerrero, México, el lunes 10 de noviembre de 2014. (AP Photo/Bernardino Hernandez)
A masked student holding up a slingshot confronts police during a protest against the disappearance, and probable murder, of 43 students in the state of Guerrero, outside the Acapulco airport in Mexico, Monday, Nov. 10, 2014. Relatives and supporters battled federal police in Acapulco, then blocked roads leading to the Pacific resorts airport, forcing tourists to walk to the terminal. The 43 teachers-school students disappeared at the hands of a city police force on Sept. 26 in the town of Iguala. (AP Photo/Bernardino Hernandez)
Una mujer porta la foto del estudiante desaparecido Cesar Manuel González Hernández, cuando ella participaen el bloqueo al acceso al aeropuerto de Acapulco en protesta por la desaparición y probable muerte de 43 estudiantes del estado de Guerrero, México, el lunes 10 de noviembre de 2014. (AP Photo/Marco Ugarte)
Magnolia Seguino, que vive en Nueva Jersey, EEUU, espera con su equipaje tras una línea de estudiantes encapuchados que bloquean el acceso al aeropuerto de Acapulco en protesta por la desaparición y probable muerte de 43 estudiantes del estado de Guerrero, México, el lunes 10 de noviembre de 2014. (AP Photo/Marco Ugarte)
EstudianteS encapuchados con escudos quitados a policías federales bloquean el acceso al aeropuerto de Acapulco en protesta por la desaparición y probable muerte de 43 estudiantes del estado de Guerrero, México, el lunes 10 de noviembre de 2014. (AP Photo/Bernardino Hernandez)
Un estudiante encapuchado confronta a la policía durante un bloqueo al acceso al aeropuerto de Acapulco en protesta por la desaparición y probable muerte de 43 estudiantes del estado de Guerrero, México, el lunes 10 de noviembre de 2014. (AP Photo/Bernardino Hernandez)
Un estudiante permanece junto a un muro con consignas durante una protesta de bloqueo al aeropuerto de Acapulco por la desaparición y probable muerte de 43 estudiantes del estado de Guerrero, México, el lunes 10 de noviembre de 2014. (AP Photo/Marco Ugarte)