A well-known conspiracy theorist died after taking a form of anti-anxiety drug while suffering from pneumonia, an inquest heard. 

Max Spiers died aged 39 in Warsaw, where he had travelled to speak at a conference in April 2016.

An inquest held on Monday in Kent heard that Spiers was addicted to heroin and crack cocaine, and died three months in Warsaw in the home of a woman he had started a relationship with. 

He had bought “eight to ten” boxes of the Turkish form of Xanax during a holiday to Cyprus with Monika Duval, 50, and took several on the day of his death, the inquest heard. 

A statement from Duval which was read at the inquest, said on the day of his death he fell asleep on her sofa after taking ten of the tablets, before she noticed he had stopped breathing several hours later.

He then began to vomit as she attempted to resuscitate him as she waited for paramedics arrive, the inquest heard.

She said: “I noticed he had something in his mouth, some remnants of food, so I turned him on to one side and saw gastric fluids pouring out of him – brown liquid, like somewhat tea coloured.”

Though paramedics arrived some ten minutes later, taking over resuscitation and administering adrenalin intravenously, the father-of-two was declared dead at the scene, the inquest heard.

Speaking in 2016, his mother Vanessa Bates said her son had complained of feeling unsafe, saying: “He had spoken to me, and he also sent me a message through WhatsApp saying: ‘Mum, I don’t feel safe.’ He even used the words: ‘I think I could be murdered’”

Duval’s statement said that on 14 July, just two days before his death, Spiers had contacted his mother, claiming he had been attacked. In a conversation with a fellow journalist around the same time, he said he had been “attacked by a named person and a Satanic group.”

Duval said of Spiers: “On average he said something like that once a week.”

At the end of her statement Duval said: “I would have done anything to save him, I really cared about him. I was deeply in love with him.”

A statement from the Polish prosecutor’s office said the death “was caused by natural causes” and “excluded participation of further persons”, the inquest heard.

Though a post-mortem examination at Margate QEQM Hospital, Kent in 2016 was unable to determine how Spiers died, the pathologist who examined him on Monday provided a provisional cause of death as being “pneumonia and intoxication by drugs, causing aspiration of gastric contents.”

Spiers was described by the Polish prosecutor’s office as a journalist “dealing with the topics of conspiracy theories and paranormal phenomena”, the inquest heard.

Duval agreed shortly after they met to let him stay at her house, rather than take his return plane ticket back to Britain.

After picking him up from his hotel, she then took him to a doctor’s surgery and bought him medication worth more than 1,500 Polish zloty (about £315).

The inquest was told he often suffered illness while staying with her and “sometimes he felt weak and sometimes he had problems with focus and attention”.

In her statement, Duval added he had once spent a day in a deckchair in her garden “unconscious”.

She paid for several other medical appointments during his stay, it was said.

The inquest heard he bought the Turkish Xanax equivalent during a holiday with Duval to Cyprus from June 27 to July 11, when he visited a pharmacy and found the drug could be bought without a prescription.

Spiers asked Duval to buy the “entire stock”, about eight to ten boxes, of the drug and she “fulfilled that request”, according to Polish prosectors.

In October 2016, his friend Miles Johnson, who also researches UFOs, added to the intrigue of the case when he told BBC Radio Four that Spiers “knew he was going to die” after working to expose “enemies within other realities”, and claimed he had been  “terminated”.

Johnson added: “We have now got an unthinkable situation. Max has died for his country and the people on this planet. We’re dealing with aliens. 

Speaking to the Guardian last week, his mother said: “I want answers. There are certain bits [of the story of his death] that are easy to follow, and other key areas that have massive gaps.”

Bates claims his laptop had been wiped before it was handed back to her and a phone belonging to Spiers was missing its sim card.

The inquest, which is scheduled to last three days, continues.