Serial killer Stephen Port was obsessed with watching drug rape pornography, sometimes with men he had met on hook-up sites, an inquest has heard.

The 46-year-old, jailed for life for murdering four men and sexually assaulting several others, watched hours of footage, and also used the drug GHB, which he had started taking in late 2013.

He went on to kill Daniel Whitworth, 21, from Gravesend, Anthony Walgate, 23, Gabriel Kovari, 22, and Jack Taylor, 25, with overdoses of the drug between June 2014 and September 2015, and then dumping their bodies near his flat in Barking, east London.

In 2016, Port, from Barking, was found guilty of the four murders.

Since then the victims’ families have continued to fight for answers as to why he evaded detection by police for so long.

The inquests into his victims’ deaths began this week. The hearings will look at whether the series of investigations into their murders were adequate and whether lives could have been saved.

Giving evidence at Barking Town Hall yesterday (Wednesday), Detective Inspector Mark Richards talked about Operation Lilford, the investigation launched after the four deaths were linked.

He said Port’s laptop, originally seized when officers first investigated the death of fashion student Mr Walgate, showed hundreds of thousands of lines of messaging about drugs, sex and pornography.

“It was absolutely incessant”, he told the jury. “It was all day, every day.”

"There were hundreds of thousands of lines of messages because he was obsessed.”

Port would watch “a considerable and extensive amount” of drug rape pornography, viewing it for hours at a time on his laptop.

The officer said: “He had a real obsession with drug rape pornography.”

On more than one occasion, Port would stop messaging or watching the footage for around 30 minutes to go and meet men at Barking station and bring them back to his flat where he would continue viewing the material once the men were in his home.

The inquest heard that as well as the murders, Port was found guilty of the drugging and sexual assault of seven living victims at his Old Bailey trial.

There were also around six other living victims identified by police who did not wish to take part in the prosecution.

Detectives looked at nearly 60 other deaths to make sure Port had not played a part, and concluded that no accomplice was involved.

Their theory was that Port had wrapped his victims’ bodies in bed sheets and carried them to the sites where they were found.

Former Dartford Grammar student Daniel was killed by Port in 2014 after they met via the gay dating app Grindr.

Earlier in the hearing, Daniel's family paid tribute to their "pride and joy" and spoke of their pain over his death being treated as suicide.

After leaving school, Daniel attended Denton College in Gravesend, where he trained to become a chef.

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