You are seeing this error because the action img is not defined in controller BuscadorsController
If you want to customize this error message, create app/views/errors/missing_action.thtml.
Fatal: Confirm you have created the BuscadorsController::img() in file : app/controllers/buscadors_controller.php
<?php
class BuscadorsController extends AppController {
function img() {
}
}
?>