diff --git a/main.go b/main.go
index a6cc153..9112c49 100644
--- a/main.go
+++ b/main.go
@@ -196,6 +196,8 @@ func (h *Handler) ServeWebSocket(wsConn *websocket.Conn, rAddr string) {
 	loc, ok := h.locations[uuid]
 	if !ok {
 		authLog.WithField("uuid", uuid).Error("unknown user")
+		wsConn.CloseNow()
+		return
 	} else {
 		authLog.WithField("uuid", uuid).Info("logged in")
 	}