Also consider that your dog might have reacted to scent rather than sight and, that could be the other dog or the owner of the other dog.
My four are fine or shy off (wolfdogs) from most strangers to them however, there are two people whom they growl and bark at aggressively if they so much as walk down the road in front of my house. All four react the same way, even when separated and, even my 12 week old puppy.
I won't go into details but, if the dogs sense half of what I know about those two people, then, I don't blame them one bit - not good people.
My four are fine or shy off (wolfdogs) from most strangers to them however, there are two people whom they growl and bark at aggressively if they so much as walk down the road in front of my house. All four react the same way, even when separated and, even my 12 week old puppy.
I won't go into details but, if the dogs sense half of what I know about those two people, then, I don't blame them one bit - not good people.