Flew from SCL-LIM-LAX last month. After security, I bought a few final souvenirs and a bottle of water while waiting for the flight.

After going through the gate, walking down the jetway, there was another layer of security inside the jetway. They had a table set up in the jetway, and you couldn't pass by until they examined your carryon. They confiscated my bottle of water. I told them that I bought it AFTER security before, but they didn't care. Meanwhile, a guy next to me was carrying a bottle of water, and another agent let him go through. I had never encountered an additional bag check when I was already inside the jetway. Does anyone know if this is common for LAN or SCL airport?