Darlow allegedly kicked a man during an altercation outside a Northumberland takeaway hours before the Magpies flew out on their pre-season tour.
"I've already spoken to Karl and I'll speak to Jonjo," Bruce said.
"I don't know everything that has gone on, but we will deal with it. I will deal with like I always have done, in house. We will found out what's gone on and if needs be, they will be disciplined."