New UPDATE
Shawn Hubler, Giulia McDonnell Nieto del Rio, Marie Fazio, and Elizabeth Dias contributed to this article. 23rd of March, 2021 2:35 p.m. ET update Authorities say a gunman opened fire at a grocery store in Boulder, Colorado, on Monday, killing ten people. A Boulder police officer, a young grocery store employee, and a retiree filling Instacart orders were among them.