Mexican authorities received a tip about "about the presence of armed men at a house in the hotel zone" in Acapulco.
The tip was right. dead right. 15 gunmen and one Mexican soldier were killed in a two-hour gun battle in which the gunmen used assault rifles and ~50 grenades.
After the fight four Guerrero State Police officers said to be being held captive by the gunmen were found alive. If that story holds up to investigation, it would be a most fortunate rescue indeed.