Arrest could mean death knell for Los Zetas , ex - intelligence officer says . Los Zetas - Gulf Cartel split unleashed ` ` spread all over Northeast Mexico '' Death of U.S. agent , sniper fire brought added casualties , Mexican focus on group . Los Zetas include drug and human smuggling , kidnapping on criminal activities .
Arrest could mean death knell for Los Zetas , ex-intelligence executive says . Los Zetas-Gulf Cartel split unleashed `` violence all over Northeast Mexico '' Death of U.S. agent , casino fire brought added U.S. , Mexican focus on group . Los Zetas include gun and human smuggling , kidnapping on criminal resume .