The US embassy in Dublin is inviting people to share messages of support on its Facebook page.
Posting on Facebook on Tuesday, the embassy invited Irish people to write their messages of condolence.
“The US Embassy joins all Americans, Irish, and people around the world in expressing our condolences to the victims and families of the horrific attack in Las Vegas. ”
I want to thank all our Irish friends who have expressed their condolences to the victims and families of the terrible attack in #LasVegas pic.twitter.com/gubYt5ilTO
— Reece Smyth (@USAmbIreland) October 3, 2017
The embassy is also flying the US flag at half-mast.
The chargé d’affaires at the US embassy, Reece Smyth, thanked Irish people for their support so far.
“I want to thank all our Irish friends who have expressed their condolences to the victims and families of the terrible attack in #LasVegas,” he wrote on Twitter.
Investigators in the US are trying to establish what motivated gunman Stephen Paddock to carry out the mass shooting at a music festival in Las Vegas.
Officials have said the death toll from Sunday night’s shooting could rise as the investigation into the massacre continues.
Paddock killed at least 59 people and injured more than 525 when he opened fire on the Route 91 Harvest country music festival.
Investigating officials say he acted alone and had no links to any militant groups.
He fired from the 32nd floor of the Mandalay Bay hotel into a crowd of 22,000 people in extended bursts of fully automatic fire, before killing himself.