Relatives of 43 missing students in Mexico hold a march demanding the return of their loved ones. Yiming Woo reports.
Parents of 43 missing students in Mexico are demanding their safe return. The trainee teachers disappeared a month ago in Iguala after clashes with police and are feared to be dead. (SOUNDBITE) (Spanish) GISELA, MOTHER OF MISSING STUDENT JORGE ANTONIO TIZAPA, SAYING: "We want our children back, that is our demand. That is what all the parents are demanding. We want our children back." Four members of the Guerreros Unidos drug gang and dozens of officers have been arrested for alleged involvement in disappearances . A manhunt continues for Iguala's mayor, his wife and the police chief. The case has sent shockwaves across Mexico and sparked protests over apparent collusion between politicians, police and drug gangs.