Britain's wealthiest millionaires are spending up to £5 billion to protect their assets, fortune and family, according to new research.

Figures from home insurer Zurich show 91 per cent of liquid asset millionaires have invested up to £30,000 on security, as more than a fifth are worried about being targeted for theft because of their wealth.

And the worry is not unfounded as nearly 40 per cent of millionaire mansions have been broken into, and almost a fifth of the wealthy population has suffered at the hands of car thieves.

Recent crime statistics show that serious crime has fallen in recent years but that does not stop 58 per cent of people worrying about being mugged, 54 per cent are concerned about having their identity stolen and 40 per cent are anxious about being car-jacked.

Kris Coombes from Zurich said people should check that they have sufficient quality risk prevention measures in place, starting with a visit from a qualified insurer to provide risk management for assets.

"Wealthy individuals should also check that lifestyle cover is included as part of their insurance; for us this includes insurance for identity fraud, cover for car-jacking to the providing of temporary relocation in the event of stalking."

Zurich suggests wealthy homeowners do several things to minimize their security risk including using a shredder to destroy personal documentation (preventing ID theft), link an intruder alarm to the alarm receiving centre (prompting a police response) and hide car keys at night.