MEXICO CITY, June 18 (Reuters) - Mexico City Mayor Claudia Sheinbaum said on Friday that she would like the firms that built the metro railway that collapsed and killed 26 people last month to participate in "economic terms" in its reconstruction.

Preliminary findings of an independent investigation presented on Wednesday showed the collapse of a section of the Linea 12 line was caused by a structural failure. (Reporting by Raul Cortes; Writing by Anthony Esposito)