The paparazzo who sent gut-churningly gory pictures of Princess Diana's dying moments feared spies tried to blow him and his office to smithereens to wipe out the evidence of their involvement in her death.

RadarOnline.com can reveal Darryn Lyons – dubbed 'Mr Paparazzi' while running London-based agency Big Pictures in the 1990s – is convinced "someone else" was involved in wiping out the doe-eyed royal.

He told us his office in the capital was almost immediately targeted by agents after her death in what he believes was a burglary and bomb plot.

On September 2, 1997, petrified Lyons voluntarily handed over copies of the Diana death pictures to a police constable from Islington Police Station – and was left feeling he was "lucky not to have been killed in all the cloak and dagger stuff" in the wake of Di's crash.

Lyons said from his home in Australia: "On the night she died, I had the world exclusive at my feet. I got the photos of the scene literally minutes after the accident. They were extraordinary and very graphic.

"But when we found out that Diana had passed away, those pictures had to be taken off the market. I made the decision these were pictures that the world should not be seeing.

"The night after, I remember unlocking the door of Big Pictures and the alarm wasn't set… and all of a sudden, I hear a 'tick, tick, tick, tick, tick.' Then, I saw with my own eyes a shadowy character. I just screamed, 'Get out!'

"I thought to myself, ‘Is there a bomb in here?' As time went on, we could hear other voices on the telephone lines. We could hear tapping on the phones. We were definitely being listened to.

"There's no question in my mind that we were under extreme surveillance… I had an immense amount of fear. I think there was an intelligence operation underway in an attempt to get what we had and download it. We began to receive death threats at our office. Every day, nonstop.

"Even though we've had inquiry after inquiry into Diana's death, I still think there's someone who was involved in the accident."

Meanwhile, one of Diana's final bodyguards also told us he fears he was put under surveillance after her death.

Lee Sansum – who was killed by a heart attack last year aged 63 – said he spotted mysterious figures when he returned to Britain after her Paris smash.

The British martial artist said: "Whether it was just two guys in a black car, I don't know.

"But if you're in the depths of a British security operation at that level, they would know where each one of us was."

Lee, dubbed 'Rambo' by Di when he was part of her team of guards on her final sunshine holiday in St Tropez with Dodi Al-Fayed, added he and his colleague Martin also spotted a "14 Company Special Reconnaissance Unit guy" near the Al-Fayed home in Oxted before the team left with the royal for her infamous boat trip with the playboy.

If Diana had survived her crash in Paris on August 31, 1997, she would have celebrated her 65th birthday today – July 1.

Instead, she was pronounced dead at 4am on a bloodied surgical table at the Pitié-Salpêtrière Hospital.

A rip in the left pulmonary vein of Diana's heart was the fatal injury that ended her short and tortured life.

She survived the moment her black Mercedes S280 – registration 688 LTV 75 – hurtled into the thirteenth pillar of Paris's 660-foot Pont de l'Alma underpass at a devastating 121 mph.

But she suffered two heart attacks and, on the way to the hospital, was in such distress she yanked out the drips pumping drugs eighty times more powerful than morphine into her veins while mumbling indecipherable last words.

Theorists highlight how she apparently had enemies ranging from scorned ex-lovers to international arms dealers due to her landmine campaign – and the Royal Family itself.

Some think a flash seen in the tunnel was a light gun used to blind the chauffeur, while others believe the fact Diana's shattered body was embalmed just hours after her tragic death is evidence she was pregnant by Dodi.

Many believe she was bumped off as ‘The Firm' didn't want his offspring being part of the Royal Family.

Others think the CIA colluded with the royal family to have her bumped off by drugging the driver.

Dodi's dad Mohamed Al-Fayed poured an estimated $14.6million into investigating 175 separate conspiracy theories surrounding Diana and his son's death.

The Harrods-owning sex predator died convinced the royal family was one of the parties involved in plotting the deaths to prevent Diana from marrying his Muslim son.

In October 1996, Diana shared her belief she was going to be murdered in a car accident in a now infamous letter.

It said: "This particular phase in my life is the most dangerous. My husband is planning ‘an accident' in my car, brake failure and serious head injury in order to make the path clear for him to marry."