It was only after the BBC broadcast in September that the Met revealed it had been approached by 21 women before Al Fayed’s death who accused him of sexual offences including rape, sexual assault and trafficking. Despite this, he was never charged with any offences.

Since the documentary aired, 90 further women have contacted the force, with allegations stretching as far back as 1977. A wider investigation by the Met into the claims against Al Fayed is ongoing.

Two of the women, whose allegations were reported in 2008, complained after the documentary about how the force had handled their claims.

The complaints relate to “concerns about the quality of police response and how details came to be disclosed publicly”, a previous statement from the Met said.

IOPC director of operations Steve Noonan said: “There is widespread public concern around this case, with a significant number of allegations reported over many years while Mr Al Fayed was still alive.

“It’s important that an investigation is carried out into these complaints to identify if there were any missed opportunities or failures by officers to properly investigate these reports made back in 2008.”