Roaches in the pizza extra topping

I went and ordered supper from pizza hut pavilion the cashier said order will take 10- 15 minutes, my order was only recieved half an hour later whilst people that came after me got their orders before me. When my order came and sat with family to eat there were roaches in the pizza me being hungry ended up angry and went back to the manager he started to be aggressive stating I should not put a show it's only a roach and I am over reacting no sorry or anything and they started to act a bit ****** to me where the managers friend threaten me and said he will hit me in front of my family because I said I came with my family for supper not to eat roaches and I'm going to lay a complaint. I am dissatisfied and it is not acceptable the way the manager and cashier handled it. They refused to give me any contact for higher management and where I can complain.