"Yeah, but he won't be if he stays here like this," Harry said and looked him over. His mind picked apart the curse immediately, recognizing the effect and immediately he worked on a counter that released him. The man gasped for air and then looked at the two of them. Harry instructed, "Apparate now. Get away from here, right now." The man didn't need to be told twice as he vanished with a zip sound.
Harry then turned and used his wand to create a shield as another curse came flying at them. He didn't know why he did it, only that they were both at risk when they were looking over the man and it was likely that someone had wanted to strike. He got lucky that he did it when he did.