Why are Lebanese so hated in Australia?

In Australia, a lot of Muslim Lebanese are involved in gang raping and other disgusting crimes and they're just always against Aussies! But why do people have a good impression of Lebanese in all the other parts of the world? I mean Lebanese are welcome in other countries and are just extremely cool and nice people (such as in the US and in Canada and in SA)! Why is it only in Australia where Lebanese are not welcome? Did something happen to them before they arrived in Australia? Please explain if you know! Thanks! I am a Lebanese fan but I ALWAYS hear Australians accusing Lebanese people for acts of crime and other bad stuff. In other countries, Lebanese are just the most wonderful people ever!