A 32-year-old man has been arrested by officers from the Metropolitan Police as part of a joint investigation with HM Revenue & Customs (HMRC) into a suspected £1m fraud.

The investigation began in June after HMRC detected an electronic attack on its system and it was reported to officers from the Police Central e-Crime Unit (PCeU) – a new team set up to co-ordinate police response to e-crime.

The investigation by the two organisations is looking into a criminal network believed to be stealing money from HMRC through fraudulent claims via the self-assessment tax repayments system.

Detective Chief Inspector Terry Wilson, from the PCeU, said the police operation had been complex.

"It shows how such e-crime attacks and frauds are being identified and taken very seriously by both organisations," he said.

"The issue of e-crime is a growing problem across all business sectors and online services but working with our partners in government and industry we are committed to ensuring that criminals do not find the internet a safe environment to operate in and that those operating internet services have the full protection of law enforcement."

The man was arrested from his home in Poplar, East London in the early hours of this morning on suspicion of fraud and money laundering. He was taken into custody at Bethnal Green police station.