For two days after the attack, the Muggles were only able to bark. Harkaway was forced to resign as President of MACUSA as a result of this incident.
Harkaway's presidency began in 1760, so the attack happened some time after that.
Several No-Majs savaged by President Harkaway’s crups
Date circa 1761
Location in Canon Pm: Pottermore
Type of Event Muggle world