My friend went to University of NSW early 2000s and she said when her friends disappeared for a while, they knew they were caught by the border patrol and depor

My friend went to University of NSW early 2000s and she said when her friends disappeared for a while, they knew they were caught by the border patrol and deported because of some sort of overstayed visas. They all knew how aggressive Australia was at enforcing visa violations. Maybe they changed the process since then but she said everyone knew they sent visa overstayers to the offshore jails to scare them and send a message to everyone else. CORRECTION: you are right. I got my story mixed up so I was wrong. It’s illegal immigrants who arrived by boat that were sent to offshore jails. My friends friend was sent to a regular jail. He had a student visa and stopped going to uni so he got arrested and deported because his visa got cancelled.