The Metropolitan Police is being investigated for alleged homophobia after a serial killer from east London murdered four young men he targeted on gay dating websites.
Scotland Yard bosses admitted the Met had “potentially missed opportunities” to catch the prolific killer and that investigators who failed to notice "striking similarities" between the men's deaths had only patchy knowledge of the use of drugs linked to gay sex.
The Independent Police Complaints Commission (IPCC) is investigating whether homophobia played a part in the errors, and the Met's advisers from the gay community have called on the force to deal with "any systemic or cultural issues" that may have come into play.
Stephen Port, a chef from Barking, was found guilty at the Old Bailey of a total of 22 offences, including the four murders.
The 41-year old lured his victims to his flat and drugged them with GHB, the court heard.
Scotland Yard believes there could be more victims and is reviewing 58 deaths in London over four years that are linked to the drug.
Seven police officers could be fired if claims of gross misconduct are proved and a further ten – ranging in rank from constable to inspector – are under investigation by the IPCC over how the deaths of Port's four victims were investigated before they were officially linked.
Commissioner Cindy Butts, from the watchdog, said: "It is important we establish whether the police response to the deaths of all four men was thorough and appropriate in the circumstances, including whether discrimination played any part in actions and decisions.
"We would like to hear from anybody who provided information to the police about Port, or any of his victims, between 19 June 2014 and 15 October 2015."
Some of the victims' loved ones, members of the Met's lesbian, gay, bisexual and transgender (LGBT) independent advisory group and journalists from website Pink News all raised concerns that a serial killer was at large, and were told that there was no link between the deaths.
The original investigations into how the four men died were dealt with by officers based in Barking and Dagenham but they failed to spot that there had been foul play.
In the cases of the first victim, Anthony Walgate, and the third, Daniel Whitworth, local officers called out specialist homicide investigators for advice, who also missed signs that something suspicious had happened.
Commander Stuart Cundy, of the Specialist Crime and Operations Command, said the Met was cooperating with the investigation.
"It's not appropriate to pre-empt what the IPCC may or may not find from their investigation at this point in time but, rest assured, we're not sitting here waiting for those findings to come through. That's why we've already taken action in areas where we know we could have done better," he said.
"I can't sit here and say categorically that lives could have been saved or other victims protected. All I can say is from the evidence we've heard at trial there were potential opportunities that were missed. The IPCC investigation will carefully consider those."
He said he was writing to the victims families to apologise for the missed opportunities to catch the so-called Grindr serial killer.
If the IPCC inquiry found failings on behalf of the Met they would “respond accordingly”, he said, adding that if the IPCC uncovered evidence against particular officer it would be “carefully considered”.
The family of Jack Taylor, the fourth man to die at Port's hands, plan to sue Scotland Yard and say the killer would not have been stopped if they had not fought for a full investigation.
Port dumped his victims' bodies in or near a graveyard within 500 metres of his flat in Barking and embarked on an elaborate cover-up.
He disposed of their mobile phones, repeatedly lied to police and planted a fake suicide note in the hand of once of his victims taking responsibility for a previous murder.
Scotland Yard's LGBT independent advisory group (IAG) said: "The IPCC report may take some time to be delivered and it is right it will deal with matters of individual conduct. We welcome the admission by the police that opportunities were missed.
"However, in the meantime, it is the view of the LGBT IAG that the police must demonstrate without delay a commitment to addressing any systemic or cultural issues that may have contributed to these sad events."
Investigators have also appealed for any other men who may have been sexually assaulted or raped by Port to come forward.