Marilyn Monroe would have turned 100 today (June 1) and as we mark what would have been a momentous occasion, we've looked back at some of the tragic theories that surrounded her death. The conspiracies have been rife ever since she was discovered on August 5, 1962, in her bed in her Brentwood home where her hand was draped over the phone. Her death came as a shock to all, but as conspiracies continued to grow, the Los Angeles County district attorney's office was forced to reopen an investigation into her death in 1982; two decades after she died.

At the time, some people believed Marilyn was killed because of her connections to President John F Kennedy and US Attorney General Robert F Kennedy. Prior to her death, she explained to friends that Robert Kennedy had cut her off, but she couldn't get the president out of her mind, telling a friend on the phone the day before her death she was "very much in love" with Bobby Kennedy.

On August 4, prior to her death, she explained to a friend Jeanne Carmen that someone had been calling all night and calling her names, with the anonymous caller saying: "Leave Bobby alone, you tramp. Leave Bobby alone." But what really concerned people was a friend, Sydney Guilaroff, stating that Marilyn had phoned her in despair in her final hours.

She wrote: "She rambled on about being surrounded by danger, about betrayals by 'men in high places' about clandestine love affairs". Marilyn had also apparently stated that it was the same day that Robert had told her their relationship was over. The actress is also said to have warned her friend that she knew "secrets about what has gone on in Washington".

Theories have also surrounded the idea that the Mafia were involved in relation to Marilyn's links to the Kennedys, with theories that Mobsters allegedly bugged her home to collect material on the Kennedys.

However, after intense investigations, the Los Angeles Times reporeted a headline in late 1982 that the prosecutor's office found that Monroe's death from "acute barbiturate poisoning" could have been an overdose or accidental, but they had time to disperse into her blood and liver which explained why the doctor found no residue in her stomach.

The three-month invesitgation didn't satisfy everyone, with some convinced that something darker occurred. In 1985, a woman claimed her ex-husband, actor Peter Lawford, went to her home the night she died and destroyed a note she had left, though it has never been confirmed whether a note was actually taken.

Her FBI file, which was shared 50 years after she died, showed that they were aware of theories alleging she was murdered, but the claims were not looked into.