More than 3,000 people have been killed since Philippine President Rodrigo Duterte declared the war on drugs that he believes is required to arrest his already threadbare country’s slide towards becoming a narco-state.

About a third of that number died at the hands of police, with the rest presumed to have been extra-judicial executions as Duterte’s “shoot first ask questions later” strategy results in the sort of body count you might expect from a state-sanctioned spree of score settling, informant disposal and vigilante bloodlust.

Among the deadly detritus of Duterte’s clean-up act, earlier this month, was the fully clothed and crumpled body of a 45-year-old woman lying on the side of a Manila street oozing blood, with a cardboard sign perched next to her that read: “drug pusher for celebrities”.

The woman was Maria Aurora Moynihan, a crystal-meth addicted, well-to-do member of Manila’s social elite and the daughter of a late, disgraced member of the British House of Lords – Antony, the 3rd Baron Moynihan.

Behind his daughter’s death in a Manila gutter lies the story of blue-blooded English aristocracy gone bad in a world of international drug traffickers, gun-running and wannabe spies with significant links to Hong Kong.

British peer Moynihan – the half-brother of Lord Colin Moynihan who served as sports minister in the cabinet of former UK prime minister Margaret Thatcher and was the former chairman of British Olympic Association – died aged 55 in 1991 after years on the run from the authorities in Britain.

He owned a string of brothels in Manila and was widely believed to have had links to the international heroin trafficking business and to have worked for the United States’ Drug Enforcement Administration.

Moynihan, whose obituary in one English newspaper described him as a “bongo drummer, brothel-keeper, drugs smuggler and police informer”, also had significant connections to Hong Kong, where he met one of his four wives.

One of his closest friends and associates was Ronald Milhench, who was jailed in Hong Kong in 1995 for possession of a firearm, ammunition and a false passport – all of which were given to him by the late baron after the pair struck up a friendship in the Philippines in the 1970s.

Milhench was lured to the city after receiving a message from the Hongkong & Shanghai Bank, explaining that it was moving premises and needed clients to clear their safety deposit boxes – which was where he had stashed the illegal goods.

Setting off on what seemed a routine business trip, Milhench scrawled a message to his partner, saying “See you soon, Much love, Ron, xx,” in lipstick on tiles of his bathroom wall.

He didn’t see her soon, because the Hong Kong police saw him first. Milhench, then 57, was arrested by Hong Kong police and jailed for five years in Stanley Prison.

Sentencing him at the High Court, Mr Justice Stuart-Moore described Milhench as a “silly schoolboy pretending to be James Bond’’ with an addiction to excitement.

Born in 1937, Milhench joined the British Army at the age of 15 and was honourably discharged in 1966. It was during this time he developed an interest in firearms.

At first, life as a civilian went well but in 1974 his fortunes turned and so did his head – to crime.

In an audacious attempt to buy a parcel of expensive industrial land in England, he forged the signature of then British prime minister Harold Wilson, then tried to sell the forged document to a British newspaper for the hefty sum of £25,000.

He was jailed for three years and on his release in March 1976, left England for the Philippines where he made a multimillion dollar fortune over the next decade.

But Milhench was not happy to sit back and enjoy his wealth. He had a thirst for danger and liked to hang out with celebrities. A year before he was jailed in Hong Kong he was photographed spending time with another baron – Frederik von Pallandt – one half of Danish-Dutch singing duo Nina and Frederik who recorded a version of Puff the Magic Dragon. Days after Milhench made a final payment to the singer for a yacht, worth around £350,000, von Pallandt was shot dead on the island of Mindoro over a money dispute. Milhench was in Australia at the time.

Milhench’s interest in luxury yachts led him to gain information about smuggling and brought him into contact with Moynihan, at that time working as an undercover agent for the DEA.

The two men had planned to take part in undercover anti-drug smuggling operations, which never came to pass.

Always up for excitement, Milhench had also set out on his own secret mission to help “blow wide open” an illegal immigrant smuggling operation.

He came to Hong Kong to meet the smugglers, the court was told at the time of his trial. The court also heard he lent them money to finance their operation in the hope of later turning them over to the police.

Instead, Milhench ended up doing a five-year term in Stanley which clearly he didn’t take to. After a failed appeal against conviction, his lawyers managed to secure a transfer deal which saw him serve out his sentence in Britain.

He was understood to have returned to the Philippines on his release and died in 2012.

Meanwhile Moynihan was also played a part in the downfall of late drug trafficker Howard Marks, whose biography Mr Nice was an international bestseller.

In the late 1980s, acting as a DEA informant with immunity from prosecution, Moynihan’s testimony led to the conviction of Marks, who later said of the aristocrat: “He’s a first-class bastard.”

Marks, who made many visits to Hong Kong during his days of criminal enterprise, was thought to have laundered significant amounts through the city’s banks. Indeed, years after his release from prison, when he had become a media personality, Marks was denied entry to Hong Kong because of his past history with the city.