Equipped with miniature protective glasses, a custom-fitted tactical vest and a small camera mounted on his head, Comando the chihuahua has become the smallest member of Mexico's national guard. He is being trained not only to help bring uniformed officers closer to the public but also to specialise in search and rescue operations. The canine recruit, who is 13 months old, climbed stairs and jumped over obstacles in a training session in Mexico City. Weighing 7kg and just 21cm tall, Comando was adopted six months ago in the northern border state of Chihuahua. He had been living with an elderly couple who, no longer able to care for him, took him to a rescue centre