meter removed for fraud - who's responsible to replace

I have just found out that one of my properties has had the gas meter removed because they had tampered with it. Company refusing to put gas back on without £1000 deposit. Tenant asking me to pay it. It's actually my intention to serve them notice for illegal activity now I've found out but out of interest what is the position re there being no gas supply at the property now. The property is in a selective licencing area and there are children in the property. There is a working electricity supply, the property has an electric cooker and I have supplied electric heaters.
I would welcome any advice/views on this please
Thank you