Security measures at Prince George's school are being reviewed after a woman was arrested on suspicion of attempted burglary.
The 40-year-old suspect, who remains in custody, was detained after breaking into Thomas's Battersea school in south London on Wednesday afternoon.
The Metropolitan Police said in a statement: "The arrest at 14:15hrs on Wednesday, 13 September relates to an incident at Thomas' Battersea School on Tuesday, 12 September when an individual gained access to its premises."
"The arrested woman was taken to a south London police station where she remains in custody. We are working with the school, which is attended by His Royal Highness Prince George, to review its security arrangements after the incident."
A Kensington Palace spokesperson said they were aware of the incident, though declined to comment further on security matters.
WATCH: Prince George appears anxious on his first day of 'big school.' Post continues...
The four-year-old prince started at the $AUD 28,607-a-year preparatory school on 7 September.
Sadly, The Duchess of Cambridge, who recently announced her third pregnancy, was too under the weather with severe morning sickness to attend her son's milestone.
Confirming she wouldn't be in attendance, Kensington Palace explained via Twitter: "Prince George will this morning attend his first day of school at Thomas's Battersea, accompanied by his father The Duke of Cambridge."
"The Duchess wanted more than anything to be there. It's a big day for her son. But she has been really very sick this week," an insider told The Daily Mail.
But Prince William proved the be the perfect support for his first-born, dropping him off in the family's Range Rover and walking him right to his classroom.
Speaking just hours after his son had attended his first day, the proud dad revealed that everything "went well" -- in fact, George wasn't the cheekiest child in attendance!
At a reception at Kensington Palace for the England Under-20 football team, the 35-year-old royal told head coach Paul Simpson that it had been a "good day."
"It went well," he said. "There was one other parent who had more of an issue with their children so I was quite pleased I wasn't the one. It was really nice actually."
He added: "It's a nice school."
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