Eric and his group weren't the only ones who were out for a hunt in this place, with all those camps in the surrounding areas, there was impossible to not find a few more hunt groups.
This was the normal way those camps operated. They would always send a few teams in the outside to track their possible captives, and then hunt them down immediately or call the main for reinforcements.
It was a wide and effective strategy that all the militia camps were using not only in this place but wherever they could.
Furthermore, it was really practical, and it kept the captives flowing towards the camp, even though not all of them would be kept.
The team or group coming for Eric's camp was made up of 4 people in an armored jeep. Each of them had an Ak47, and some other weapons.
They had observed Eric's camp for a while, as they were trying to decide whether they should just storm up and capture these guys, or call for backup.