Las Vegas Metro Police and medical workers stage in the intersection of Tropicana Avenue and Las Vegas Boulevard South after a mass shooting at a music festival on the Las Vegas Strip in Las Vegas, Nevada, U.S. October 1, 2017. REUTERS/Las Vegas Sun/Steve Marcus     TPX IMAGES OF THE DAY
Las Vegas is on high alert for the New Year celebrations following the October's deadly shooting. Steve Marcus/ Reuters

Western cities step up security for New Year’s Eve after year of attacks