My Stella did this when she knew we would be going to the park. she would pull and yelp and honestly sounded like she was being tortured. So embarrassing. So we made regular trips to the park, no playing. We would just walk there and leave. The behavior calmed down the more trips we made. Also once we hit the walk way, I would stand still every time she pulled, it took about 10 minutes to get to the other end, but she finally got the idea.
Sounds like a bit of leash aggresion, I give a leash correction and a leave it command to Cyrus when he does this on leash with other dogs.