Accenta - tamper fault and remote key pad frozen?

alarm has been atcivated. Internal siren and siren to front of the property has stopped however siren at the back continued. Remote key pad shows tamper fault.

External boxes, PIR's etc. and show no signs of tampering. Remote pads do not work, (keys do not operate). Power to main box has been removed and external siren to the back has stopped. Power on again but tamper LED still lit and key pad buttons still not working.