Can tenants install security systems without landlord's approval?

[Jacky Johnson]

I have had a tenant who installed several wireless surveillance cameras and motion detectors on the property without my approval or express written consent. Does this situation fall into the clause on the lease "Except as provided by law, no repairs, decorating or alterations shall be done by Resident without Owner/Agent's prior written consent. Resident shall notify Owner/Agent in writing of any repairs or alterations contemplated."? Has he breached the lease? What should I do in this situation?