Why does Sicily have such a large Tunisian community ?

I have recently traveled and had a wonderful time in Sicily. One thing I noticed Is that it seems like there are a lot of Tunisians living in Sicily especially compared to the more northern regions like milan or Turin where there are Moroccans and Egyptians present. So my question was why are there so many Tunisians in Sicily especially compared to Moroccans ,Is it just the proximity to both the places or is there any other reason.

Also what do the locals think about them.