Published: Feb 08, 2011 7:26 PM EST
Updated: Feb 08, 2011 4:35 PM EST

EL PASO, Texas- A friend says two of three teens shot dead in Ciudad Juarez, Mexico, had crossed the border from Texas for a party then stayed to buy a car.

Sixteen-year-old Carlos Mario Gonzalez Bermudez was a sophomore at El Paso's Cathedral High School, and 15-year-old Juan Carlos Echeverri had been a freshman there last year. Both were Americans.

The nationality of 17-year-old Cesar Yalin Miramontes Jimenez was unclear.

All were killed Saturday at a Juarez car dealership.

Cathedral High student Arturo Yanar said Tuesday he was friends with Gonzalez and Miramontes, and that they had been at a party together Friday night.

He says he didn't know Echeverri. He says he returned to the US after the party and that the others stayed because Gonzalez wanted to buy a used car.

(Copyright 2011 by The Associated Press. All Rights Reserved.)