Metallica announced that they have added two more dates to their Mexico City run in July and August making it a total of eight shows. The two new dates include July 28 and 30 at Sports Palace. The band promises to unveil a new stage set and massive new stage show in Mexico. Here is the Mexico City ticket information from metallica.com:

Fan Club pre-sale begins Wednesday, April 18 at 11:00 AM local time and members should log in here for details on how to participate. The Banamex pre-sale begins Thursday, April 19 at 11:00 AM local time, and any remaining tickets go on sale to the public on Friday, April 20, also at 11:00 AM local.