Monitor connection attempts from denied/blacklisted devices


On one of the interfaces of my Openwrt router, I've configured a list of denied mac addresses (blacklisted). I want to trigger a notification every time one of these devices attempts to connect to the router, but there seems to be no trace of these attempts. I've checked the logs (using logread, with high verbosity) and tcpdump, but nothing is logged. Does anyone know where these events are logged/traced?

config wifi-iface 'ap_two'
        option device 'radio0'
        option network 'lan'
        option mode 'ap'
        option ifname 'wlan0'
        option encryption 'psk2+ccmp'
        option ssid 'Router'
        option key 'password!'
        option isolate '1'
        option macfilter 'deny'
        list maclist <mac1>
        list maclist <mac2>