You may have heard of some fraudulent activity where criminals can target properties where there is no mortgage or the owner lives elsewhere - perhaps spending time abroad or sadly due to health issues moving to a care home. It has also been seen where a property has been rented out, and the tenants act criminally to sell the property.
Fraudsters may attempt to acquire ownership of a property either by using a forged document to transfer it into their own name, or by impersonating the registered owner, and then sell the property without the original owner knowing.
There is more information here:-
and you can protect your property by registering for alerts with HM Land Registry:-
Thankfully this is not very common, but it may be worth taking this step to protect your property.