A gay serial killer tried to pin the blame for one murder on another one of his victims by planting a sham suicide note, a court heard.

Stephen Port, 41, is accused of drugging a string of young gay men to satisfy his fetish of raping their unconscious bodies, and killing four of them.

The Old Bailey heard Port would meet his victims on gay dating networks Grindr, Fitlads and other websites, before taking them back to his flat and spiking them with the drug GHB, - known as "liquid ecstasy".

Between 2012 and 2015, Port is said to have carried out a string of sexual offences against 12 young men.

Four of them - Anthony Walgate, 23, Gabriel Kovari, 22, Daniel Whitworth, 21, and 25-year-old Jack Taylor - died from drug overdoses, a jury was told.

The court heard Port tried to pin the blame for the death of Mr Kovari on former Dartford Grammar pupil Daniel Whitworth, from Gravesend, by planting a sham suicide note on him apparently confessing to the killing.

Mr Whitworth's body was found by dog walker Barbara Denham dumped in a churchyard near Port's flat in Barking, east London on September 20 2014 - just three weeks after she found Mr Kovari's body in the same spot.

Police found a bottle of GBL, the liquid of GHB, and Mr Whitworth was clutching an apparent suicide note in his left hand, the court heard.

Port had met Mr Whitworth on the Fitlads website, and they arranged to meet, it was said.

He was reported missing by his partner after he failed to return home or turn up for work on September 19 2014, the court was told.

On the same day, Port deleted the account with Fitlads he had used to contact him, Mr Rees said.

"An expert in handwriting evidence had concluded that the note was not written by Mr Whitworth, but by the defendant" - Mr Rees, prosecuting

The suicide note said: "I am sorry to everyone, mainly my family, but I can't go on anymore, I took the life of my friend Gabriel Kline, we was just having some fun at a mate's place and I got carried away and gave him another shot of G.

"I didn't notice while we was having sex that he had stopped breathing.

"I tried everything to get him to breathe again but it was too late, it was an accident, but I blame myself for what happened and I didn't tell my family I went out."

The note claimed he would go to prison if he went to the police, and he could not do that to his family, the court heard.

The note added: "Please do not blame the guy I was with last night, we only had sex then I left, he knows nothing of what I have done.

"I dropped my phone on way here so it should be in the grass somewhere."

It said he had taken an overdose of GHB and sleeping pills, the jury was told.

Mr Rees said police initially accepted the apparent suicide note at face value, and did not investigate further.

He added: "But the note turned out to be a sham.

"An expert in handwriting evidence had examined the note and compared it with samples of handwriting from others.

"He had concluded that the note was not written by Mr Whitworth, but by the defendant.

"The prosecution say that the suicide note was a clear attempt on the part of the defendant to conceal his part in the deaths of the two men."

Port was also clearly referring to himself in the note when he asked for the "guy I was with last night" not to be blamed, the prosecutor added.

The note had also mentioned Mr Whitworth's phone was missing, which Port knew would not be found on him, the court heard.

Port, of Barking, east London, denies four counts of murder, four alternative counts of manslaughter, ten counts of administering a substance with intent, seven counts of rape and four counts of assault by penetration.

The trial continues.