The suspects — a 31-year-old man and a 29-year-old woman — broke in near where the 95-year-old walks her beloved corgis. Prince Andrew was home at the time, but the Queen was not the outlet reported.
The pair was arrested and reportedly released on bail.
This is the second security scare in the past month. Six days before the April 25 incident, a Spanish woman who claimed to be Andrew's fiancée was able to enter his Windsor home after officers let her in by accident.
The 44-year-old visitor spent 20 minutes walking around before she was stopped in the lobby, where she was later arrested on suspicion of burglary.
“This is an astonishing lapse. Everyone was on high alert after the first intruder, now this happens. Heads could roll. It is unforgivable,” a source told the outlet. “The couple wandered around for ages before anyone spotted them and police were called. Andrew was at home at the time. You have to wonder what on Earth is going on up there.”
Princess Diana's bodyguard Ken Wharfe also shared his thoughts on the break-ins. “It is totally unacceptable and makes the Queen vulnerable. This is very worrying and things really need to change,” he said.
Even though the Queen prefers to stay at Windsor, she could stay at Buckingham Palace from now on.
“No one would wish to deprive the Queen of seeking solace wherever she chooses but it is worrying that security should be so lax around a building where she is such a frequent visitor," royal biographer Penny Junor said. “Andrew was in. By the grace of God, the Queen wasn’t. But she might well have been."
“She has been spending increasing amounts of time with Andrew since the Duke’s death," she continued. “Today security at Buckingham Palace is state-of-the-art — and possibly the only royal residence that is.”