The Metropolitan Police have issued a warning that fraudsters are stealing the personal details of landlords whose properties are managed by letting agents.

The fraudsters then email other letting agents in a bid to con them into believing they own the property. Through several emails, the fraudsters build up a relationship with the letting agency which, crucially, also has a sales division. After a short period, they inform the agent that they wish to sell the property or want to raise a mortgage on it.

A spokesman for the Met said: “This is a complex fraud which suggests the fraudsters have a very good understanding of estate agency. They understand how the agent, solicitor and mortgage adviser and lender interact with each other, and the weaknesses in their processes.”

Agents and landlords are being urged to tighten their security.

But to underline the importance of employing a reputable estate agent, other fraudsters have been in the news this week too.

Zulfigar Hussain, formerly of Charles Lawson Lettings and James C Penny in Oxford, was ordered to pay more than £300,000 in fines, compensation and penalties under the Proceeds of Crime Act, after stealing tenants' deposits. Failure to repay his victims within six months could result in three years in jail. Hussain was also given a nine-month sentence suspended for two years.

The sentence was welcomed by the head of the Tenancy Deposit Scheme, who said it sent the right message to rogue agents.

“At last the courts are taking letting agent fraud seriously and handing down deterrent sentences,” said Steve Harriott, chief executive of the TDS. “For too long, courts have been imposing lenient sentences on agents who steal tenants’ deposits and landlords’ rents and management floats.”

Harriott added: “Every step taken to hound the very small minority of fraudulent agents who rob tenants and landlords and destroy confidence in the great majority of letting agents who are professional, honest and ethical, helps the whole industry. The reputation of the regulated professionals in the private rented sector must be protected.”