MEXICO CITY — Mexican government officials say 72 migrants found dead at a ranch near the U.S. border may have been killed by the Zetas drug cartel.

Navy Vice Adm. Jose Luis Vergara said Wednesday a wounded survivor reports that gunmen who identified themselves as Zetas kidnapped him and other migrants and took them to the ranch in San Fernando, a town south of Brownsville, Texas.

Vergara said that investigators believe the migrants were from Brazil, Ecuador, El Salvador and Honduras.