Three police officers who received complaints about paedophile rockstar Ian Watkins four years before his arrest for sex offences will face disciplinary proceedings, a police watchdog said.
The Independent Police Complaints Commission (IPCC) said South Wales Police was given information about the former Lostprophets frontman in 2008.
He was arrested in 2012 and jailed the following year, and is serving a a 35-year prison sentence after admitting a string of offences, including the attempted rape of a fan's baby.
The IPCC says the three officers - one detective sergeant and two detective constables - have cases to answer.
South Wales Police Assistant Chief Constable Jon Drake said the force conducted its own investigation into the way "a substantial number of reports and allegations" about Watkins were handled, and voluntarily referred the matter to the IPCC.
He added South Wales Police accepted the IPCC's recommendations and the misconduct proceedings will take place in the autumn.
Children's charity NSPCC Wales has voiced concern about the IPCC's findings.