There was a LOT of confusion when this happened, so some (a lot?) erroneous info got out

Apparently the pilot saw what was coming, and engaged reverse thrust, causing some who saw that to conclude the plane has just landed. Even early reports of airplane "taxiing"

Plane was very much taking off. And it is starting to look like the fire company was doing training exercises, not "responding to an unrelated emergency" as stated / posted / reported early on.