Does AWS S3 Same-Region Replication (SRR) uses public or private internet to transfer data?

Question

I'm in need of transferring some highly sensitive data and trying to avoid public internet for egress/ingress traffic.

Trying to find out if AWS uses the private(internal) network to replicate objects or uses the public internet to transfer them, but to no avail.

Answer 1

I couldn’t find a clear document explaining this but got confirmation from AWS that, SRR uses backbone internet (the internal private network) for such transfers.