LAS VEGAS (CBSNewYork/AP) — Las Vegas authorities have set up a hotline to report missing people in the wake of a mass shooting that left at least 59 people dead and more than 500 injured at a country music festival Sunday night.

Las Vegas police said Monday that it will take time to identify all of the injured and dead in what is now the deadliest mass shooting in U.S. history.

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The number to report missing people is (866) 535-5654. Police have also opened a “family reunification center” for people to find loved ones at 400 S. Martin L. King Blvd., in Building B.

Las Vegas police say anyone who wants to help can give blood at one of two locations in Vegas and nearby Henderson. A blood drive is also being planned.

Authorities say the gunman, 64-year-old Stephen Paddock, opened fire from the 32nd floor of the Mandalay Bay Hotel and Casino across the street from the Route 91 Harvest Music Festival Sunday night.

Police said Paddock was found dead in his hotel room.

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