At 9:53pm ET, Arianespace launched their Vega rocket carrying an Earth observation satellite for the United Arab Emirates, named FalconEye1. It launched successfully from the Guiana Space Center in Kourou, French Guiana, and had performed nominally up until first stage cutoff.
From the ground, it had seemed the second stage did not ignite after cutoff and the webcast switched to a graphic showing the animation of the rocket continuing, but the telemetry data shown on the side of the webcast showed it not following the planned trajectory. It was then announced that they had a "slight telemetry loss" with the vehicle, which means the flight data wasn't being transmitted from the rocket to the ground.
It was then sadly announced that Vega had suffered a failure that resulted in the loss of the vehicle and payload. Here's a clip of that announcement from Arianespace.