NEC3 ECC Option A

We have a contract where the Employer has taken over parts of the works prior to the Defects certificate has been issued. A part of the works taken over by the employer has been vandalised so who is responsible for the repairs to the damaged works? We have a Z clause which states "Add after the words “Plant and Materials” in line 12 of clause 80.1:
“other than loss of or damage which gives rise to a claim for compensation under the Criminal Damage (Compensation) (Northern Ireland) Order 1977 (as the same may be amended from time to time) or any scheme for the time being in force for the compensation of criminal damage to property in Northern Ireland”.