Albert Barnes Commentary 2 Samuel 20:12

"And Amasa lay wallowing in his blood in the midst of the highway. And when the man saw that all the people stood still, he carried Amasa out of the highway into the field, and cast a garment over him, when he saw that every one that came by him stood still." — 2 Samuel 20:12 (ASV)

All the people. This refers to the troops that Amasa had been leading to Jerusalem. They were irresolute about what to do, and the halt at Amasa’s body almost caused them to refuse to follow Joab. But after the body was promptly removed and hidden, they passed on and followed Joab, their old captain.