April 20 (UPI) -- Mexican President Claudia Sheinbaum said Monday she has requested detailed information about a security operation in Chihuahua involving U.S. agents that left four people dead, including two Americans, and stressed that federal authorities had not been informed in advance of the plan. Speaking at her daily morning briefing, Sheinbaum said the operation was carried out by the Chihuahua state government without notifying the National Security Cabinet. She ordered a review to