Dozens of patrol vehicles descended on the Strip after authorities received reports of an active shooter near the Route 91 Harvest Festival.
Some officers took cover behind their vehicles while others carrying assault rifles ran into the Mandalay Bay Hotel and Casino.
University Medical Center spokeswoman Danita Cohen said the Las Vegas hospital is taking in «several» people with gunshot wounds. She didn’t have any other immediate information.
Authorities shut down part of the Las Vegas Strip and Interstate 15.
Some flights destined for the McCarran International Airport were diverted due to incident.
Witnesses say country singer Jason Aldean was playing near the end of the concert when gunfire rang out.
No further information was immediately known.