Five people have been arrested and questioned over alleged accounting fraud at the Patisserie Valerie chain, the Serious Fraud Office (SFO) has said.

The arrests took place last Tuesday after a joint operation with the Hertfordshire, Leicestershire and Metropolitan police services, the SFO said.

Luke Johnson, Patisserie Valerie's former chairman and a columnist for The Sunday Times, was not among those arrested, according to the newspaper.

Mr Johnson had previously described the discovery of fraud at the high street cake chain as being like entering a "nightmare parallel universe".

It was put up for sale earlier this year after collapsing following the discovery of allegedly fraudulent activity in its accounts.

It has been bought out of administration by an Irish private equity firm, safeguarding nearly 2,000 jobs.

The Sunday Times said the collapse of the firm, which had 206 outlets and 3,000 staff, triggered the loss of hundreds of jobs and wiped out hundreds of millions of pounds of investors' money overnight.

The cake firm's parent company, Patisserie Holdings, has been grappling with the fallout of the alleged accounting fraud since October.

A SFO spokesman, who did not say who had been arrested or what they were detained for, said: "On Tuesday June 18, as part of a joint operation with Hertfordshire, Leicestershire and the Metropolitan police services, five individuals were arrested and interviewed in connection with the Serious Fraud Office investigation into individuals associated with Patisserie Holdings PLC."