tor-arm warning

[Zenaan Harkness <zen@freedbms.net>]

Trying to set up a Tor relay node, and the tor package recommended
tor-arm, which I installed too.

Running "arm" gives the following warning:
17:27:19 [ARM_NOTICE] Arm is currently running with root permissions.
This is not a good idea, and will still work perfectly well if it's
run with the same user as Tor (ie, starting with
 "sudo -u debian-tor arm").

When I run the above suggested command (as root), I get the following:
sudo: unable to execute /usr/bin/arm: Permission denied

Anyone using tor/arm and/ or know what I'm doing wrong?

TIA
Zenaan