An Azerbaijan Airlines plane that crashed on Christmas Day was “likely shot down by a Russian military air defence system,” a UK-based aviation security firm has said. The community is coming together to remember a man killed in a Waukesha County crash that happened on Tuesday, Dec. 24.

The flight was en route from the Azerbaijani capital of Baku to Grozny, in Russia’s south, when it diverted and attempted an emergency landing in Kazakhstan.

Mobile phone footage circulating online appeared to show the aircraft making a steep descent before smashing into the ground in a fireball. Some of the videos posted on social media showed survivors dragging fellow passengers away from the wreckage.