How do i find out where the police took my cousin?

my cousin was with his friend and then he got arrested and they took him. his friend he was with is the one that informed me on what had happened. so now i know my cousin has no way of contacting any of us. how can i find out where he is?? i live in southwest houston texas if that helps. im pretty sure it happened in the area. so do yall think he is in harris county jail or something??