A serial killer obsessed with having sex with unconscious men was today convicted of drugging and murdering men he met on gay dating websites.

Stephen Port, 41, was tried at the Old Bailey over the deaths of four men, including Daniel Whitworth, who was only 21.

Today, Port was convicted of the murders of Mr Whitworth, 21, Gabriel Kovari, 22, Jack Taylor, 25, and Anthony Walgate, 23, who had each visited Port's one-bed flat.

Scroll down for audio of Port's 999 call

He was also found guilty of raping three other men after drugging them for sex, but cleared of two other rapes. Port was also convicted of four counts of administering a substance with intent and one of assault by penetration.

Port stood emotionless before he was led away to the cells after the final verdicts were read out.

Thanking the jury Mr Justice Openshaw said: "This had been a harrowing trial. Sentencing will not be straightforward in this case. "

He will be sentenced at the Old Bailey next Monday.

It has since emerged he is now being linked to 58 other drug-related deaths.

Mr Whitworth, a chef and former Dartford Grammar School pupil, from Gravesend, was found by dog walker Barbara Denham dumped in a churchyard near Port’s flat in Barking, east London on September 20 2014.

It was just three weeks after she also found the body of another of Port’s victims, Gabriel Kovari, 22.

They died of a drugs overdose, along with Mr Walgate and Mr Taylor.

Port, of Barking, east London, drugged the young men with GHB - known as “liquid ecstasy” - so he could fulfil his sexual fetishes of having sex with their unconscious bodies.

During the trial, Port tried to pin the blame for Mr Kovari’s murder on Mr Whitworth by planting a sham suicide note, but the dates in his story did not add up and Mr Whitworth had an alibi.

Giving evidence Mr Whitworth’s boyfriend Ricky Waumsley said that evening when Mr Whitworth supposedly carried out the killing, he was actually in The Woodlands pub in Wrotham Road, Gravesend, with Mr Waumsley, and his own uncle.

Port denied 29 charges against a total of 12 young men including murder, manslaughter, rape and sexual assault between 2012 and 2015.

"We are bereft at the loss of such a clever, talented and much loved boy" - Mr Whitworth's family

Speaking after the verdicts were reached, Mr Whitworth's father Adam Whitworth, and stepmother Amanda Pearson said: "Our small family has had to endure unspeakable grief - various stages of 'coming to terms' and facing up to some of the most incredible turn of events in the space of two years.

"It has been difficult to say the least and has had a huge impact on our lives, which will never be the same again. We are emotionally and physically exhausted.

"Today has marked the end to a large part of our battle. Stephen Port has been found guilty and we are one step closer to making sure he will never have the opportunity to put another family through this again.

"We and other families affected have formed a small circle of camaraderie and friendship. This too has seen us through some of the dark days, something else for which we are extremely grateful.

"As for our boy Daniel, we feel unable to comment in any detail at this time, suffice to say, we are bereft at the loss of such a clever, talented and much loved boy."

An Independent Police Complaints Commission investigation into the police's handling of the case is ongoing.

After the hearing, Commander Stuart Cundy, of the Met’s Specialist Crime and Operations command, said: "Stephen Port was motivated by his overwhelming desire to have sex with younger gay men while they were unconscious through drugs.

“He bought drugs on a regular basis and used them to stupefy his victims without their knowledge so he could rape or sexually assault them.

“The jury found that on four occasions he deliberately set out to administer such a large quantity of drugs that it killed his victims. He then dumped their bodies a stone's throw from his flat before going to great lengths to cover his tracks.

"Port is a highly devious, manipulative and self-obsessed individual who has not once shown a shred of remorse for his actions.

"Four families have been left devastated by the loss of their loved ones in such awful circumstances and seven more men have suffered horrific sexual assaults, the trauma of which will stay with them for a long time.

"They have my deepest sympathies and I have nothing but praise for those men who came to court and so courageously gave evidence to help convict Port today."

Commander Cundy said police had worked closely with the LGBT community during the investigation, adding: "I hope Port’s conviction today offers reassurance to the LGBT community that if you have been a victim of crime our officers will take you seriously, treat your situation with the utmost sensitivity and do their very best to bring offenders before the courts.

"We can't rule out the fact there may be other victims out there who suffered at Port's hands and have yet to come forward. We would appeal for them to contact us as soon as possible."

The Met Police has also apologised to the families of Port's victims for "missed opportunities".

Commander Cundy added: "Now we have the verdict I am personally writing to each of the families of the four young men who died as well as Daniel Whitworth's partner to express our sincere condolences.

"The letters, which we are giving them today, apologise to them for those missed opportunities. I have offered to meet them if they would like to do so, both now and at the conclusion of the IPCC investigation."

Anyone who thinks they may have been a victim of Port can call police in confidence on 020 8358 0400, Crimestoppers anonymously on 0800 555 111 or third party organisations such as Galop on 020 7704 2040.