Firms have been warned to be extra vigilant securing their offices over Christmas after evidence of an increase in business crime in the past year.

Insurance firm AXA said there was a 20 per cent rise in crime-related settlements among firms, with theft showing an even bigger increase.

The average insurance settlement was around £4,000, with arson, malicious damage and break-ins among the main reasons for claims.

Bradford had the highest proportion of crime-related claims made by businesses in the three months to September with 28.64 per cent, a rise of 6.18 per cent compared with 2006.

It was followed by Bristol (28.43 per cent) and Cardiff (26.32 per cent) and Derby (25.32 per cent).

Birmingham finished eighth out of the 15 cities surveyed, with the number of crime related claims falling 2.17 per cent to 22.25 per cent.

For the first time since the index started, businesses in London (15.1 per cent) had the lowest proportion of crime related claims, recorded between July and September this year, narrowly beating Norwich (15.12 per cent).

The two Scottish cities in the table follow with Glasgow (19.59 per cent) coming ahead of Edinburgh (19.73 per cent).

Incidences of theft have increased by 27 per cent on the same period in 2006 and up 45 per cent on quarter two of this year.

The average crime claim settlement now totals £3,998, up from £3,524 at the same time last year.

Theft-related crime claims remain the most common cause, accounting for nearly two-thirds (62 per cent) of the total.

Malicious damage, which includes acts of vandalism such as graffiti and deliberately smashed windows, accounted for 33 per cent of crime claims in the third quarter of this year.

Cases of arson remain relatively rare, but account for nearly half (40 per cent) of the total settlement amount.

Doug Barnett, risk manager at AXA, said: "Crime-related claims have been consistently higher this year compared to 2006.

"This is particularly worrying as we approach the Christmas period, which is traditionally one of the busiest periods for business crime.

"With many people taking holidays and some businesses closing entirely, premises will be left empty and under-staffed.

"Retailers are also vulnerable as stores carry increased levels of stock and as customer traffic affords more opportunity for thieves.

"We are urging business owners of all types of business to review their security precautions ahead of the festive period so they don't give criminals a Christmas present this year."

Gareth Elliott, a policy adviser at the British Chambers of Commerce, said: "Sadly, business crime continues to escalate and in this the festive season the police need to be extremely vigilant.

"Despite the increase in criminal incidents, with no clear police statistics available to illustrate the problem there is growing concern amongst company owners and employers that business crime will remain a sidelined issue."

Meanwhile businesses in the Midlands have been warned not to fall for a new credit card scam that is doing the rounds.

Mike Cherry, West Midlands Business Council's Regional Business Crime Forum chairman, said: "Phone calls are being made asking for just the last three numbers on the back of the card - claiming they are from your bank or Visa. This is not true.

"In reality these are criminals who have got hold of the main card number, but need the last three numbers to steal your money.

"A bank or Visa would not ask you this information - as they have it already.

"Don't fall for this trick - please be careful if you receive calls out of the blue asking for your bank details."