The Sunday Telegraph reports on findings HJK Investigations, the housing fraud specialist, that there are "indications of fraud" in a fifth of social housing tenancies. These indicators the tenants having mortgages, utility bills or active credit at other addresses. This based on data matching of 27,000 tenants – using public information such as land registry and credit rating records.

A previous estimate was 160,000 illegal sublets nationally – this new research suggests that could be the number in London alone.

The Government are proposing a change in the law to make illegal subletting a criminal rather than a civil offence.

The reporter, Andrew Gilligan adds:

Last week, Shelina Akhtar, a councillor in the London borough of Tower Hamlets, admitted subletting her housing association property as she was convicted of £1100 in housing benefit fraud.

She paid a subsidised "social rent" of £400 a month, but lived in private accommodation elsewhere and charged her tenant £1000 a month.

Ms Akhtar has refused to resign as a councillor even though her conviction was her second fraud offence. Swan Housing, her landlord, refused to say whether it would evict her, because of "tenant confidentiality". Ms Akhtar refused to comment.