Allegiant Air has offered to assist those and their families who have been affected by the massacre in Las Vegas on Sunday night, according to the company's Facebook page.

The airline offers round-trip service from the Casper-Natrona County International Airport to Las Vegas twice a week.

"Las Vegas is Allegiant's hometown, and on this tragic day we are heartbroken but gratified to see the world rally around our community with so much support and love," the company said.

"Since day one of our operations, we have flown millions of people to and from this great city -- both visitors and those who call Las Vegas home.

"If you or your family members were affected by what happened last night, we want to help. Whether you need to fly to or from Las Vegas, please write us at communications@allegiantair.com.

"We will do what we can to help you."

Allegiant flies round trip from Casper to Las Vegas on Thursdays and Sundays.

The company will end its Casper service in January.