Superspreader events + no masks + no physical distancing + poor contact tracing = well, what do you think will happen? Same answer for every country that used this equation.

Medical Mythbusting Commentary for October 9, 2020

Source:
From the Rose Garden to rallies: What large gatherings can teach us about the spread of coronavirus

Reference:

Lessons learnt from easing COVID-19 restrictions: an analysis
of countries and regions in Asia Pacific and Europe