It must have been that handful of idiots that every club has.
The same handful, maybe, who dropped concrete on a waiter's head in Bulgaria. The ones who bricked our team's bus in 2018. The ones that wished Ederson dead as he was stretchered off the pitch wearing an oxygen mask. The ones who bricked a supporters coach after the 25 anniversary of Hillsborough. The ones who caused the deaths of 39 Juventus fans in 1985. The ones that cheered Yaya Toure being injured. The ones that looted and fought their way across Europe in the 1980s and managed to get every English club banned from Europe. The ones that stood by Luis Suarez as he racially insulted Patrice Evra.
It won't have been Liverpool fans, though, because it's never their fault.