The headline about ISIS taking credit was in the Israeli national news and Arutz Sheva almost instantaneously. I believe 3AM Pacific time per the rolling headline I saw.
Arutz Sheva also carried this brief statement on 10-2-17 at 13:19: (notation in Israel is 2/10/17, day-month-year)
Report: ‘Samir al-Hajib,’ shooter from Las Vegas
http://www.israelnationalnews.com/News/Flash.aspx/399561
According to an unofficial report from Reshet Bet, the Las Vegas shooter’s name is Samir al-Hajib.
“He is an American who converted to Islam at the age of 30 and lives in Las Vegas.”
(Reshet Bet is an Israeli FM radio station)