[13-stable amd64] pkg fails to update the HardenedBSD repository

Installed a fresh VM with 13-stable (amd64), upon bootstrapping pkg it errors with the following lines:

# pkg update
The package management tool is not yet installed on your system.
Do you want to fetch and install it now? [y/N]: y
Bootstrapping pkg from pkg+http://pkgs.hardenedbsd.org/HardenedBSD/pkg/FreeBSD:13:amd64, please wait...
Verifying signature with trusted certificate pkg.hardenedbsd.org.2014-09-04... done
Installing pkg-1.17.1...
Extracting pkg-1.17.1: 100%
Updating HardenedBSD repository catalogue...
Fetching meta.conf: 100%    163 B   0.2kB/s    00:01    
Fetching packagesite.pkg: 100%    6 MiB   2.2MB/s    00:03    
pkg: No signature found
Unable to update repository HardenedBSD
Error updating repositories!

I am not familiar with the pkg internals; how are the signatures distributed?