Prince Andrew's major security breach after woman claiming to be engaged to royal walks into his home

Prince Andrew has had a major security scare after a woman was arrested inside his Windsor home.

The intruder walked around the gardens of the Duke of York's residence, the Royal Lodge in Great Windsor Park, for approximately 20 minutes before going inside the Grade II listed building where the royal was inside at the time, The Sun reports.

The woman reportedly got past security around 11am on Monday by insisting she was there for lunch with the royal and later claimed to be engaged to the divorced Duke.

While in the lobby of the Royal Lodge, it's understood the woman asked a member of staff where Andrew was and revealed she had flown over from Spain days earlier to marry the Prince. That's when staff detained her and police were called.

The intruder told police her name was Irene Windsor and claimed she lived at the estate with fiancé Prince Andrew.

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Police allegedly found maps of other royal residences in the woman's handbag, along with a self-defence key chain in the shape of a cat but featuring two sharp prongs which can be used like a knuckle duster.

The woman was arrested on suspicion of burglary and later sectioned under the Mental Health Act.

"Thames Valley Police were called to the Royal Lodge at Windsor Great Park on Monday morning to reports of a female trespasser," a spokesman for Thames Valley Police confirmed to 9Honey.

"The woman, aged 43, was intercepted and arrested. She was subsequently de-arrested and has been sectioned under Section 136 of the Mental Health Act.

"The investigation into the incident continues, but there was no risk to any individual on the site. Due to the female being sectioned, we will not be commenting further at this time."

It's understood a security review is now underway following the incident, which is "being dealt with as a major security breach".

"She was apparently very smartly dressed, in suit trousers, a yellow blouse and peach jacket, and had her hair done up and full make-up," a source told the publication.

"The woman demanded they pay her cab fare as she was a close friend of Prince Andrew, and they obliged before helpfully pointing her on her way towards the Royal Lodge," the source added.

The Duke of York lives at the Queen Mother's former residence with his ex-wife Sarah Ferguson.

The couple's younger daughter Princess Eugenie has been living there in lockdown with her husband Jack Brooksbank and their newborn son August.

Buckingham Palace has declined to comment.