What security breach? The Queen laughs off Buckingham Palace security scare with garden party guests just hours after intruder scaled a fence and prowled around grounds for seven minutes while she was inside  

Smiling broadly while mingling with guests, The Queen today brushed off a bungling security breach at Buckingham Palace as she hosted a formal garden party in the grounds of her London residence.

Looking resplendent in a mint green and lilac ensemble, Her Majesty chatted and laughed with guests as she opened the gates to the Palace gardens and welcomed around 8,000 people.

The 90-year-old monarch appeared unfazed as she hosted the party less than 24 hours after a worrying security breach in which an intruder was able to gain access to the Palace and roam the grounds for seven minutes.

Earlier today, Ken Wharfe, a former bodyguard for Princess Diana and Princes William and Harry, said the man was allowed to wander around the garden for too long after scaling a perimeter wall.

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Smiling broadly while mingling with guests, The Queen today brushed off a bungling security breach at Buckingham Palace as she hosted a garden party for 8,000 guests in the grounds of her London residence

Looking resplendent in a mint green one-button coat and a cerise dress by Karl Ludwig Couture with a matching hat by Philip Sommerville, Her Majesty laughed with guests as she opened the gates to the Palace

The 90-year-old monarch appeared unfazed as she hosted the party less than 24 hours after a worrying security breach in which an intruder was able to gain access to the Palace and roam around for seven minutes

The 41-year-old intruder - named by police as Dennis Hennessy - got into the Palace grounds shortly before 9pm yesterday evening, when the Queen and Prince Philip are understood to have been there. 

He was arrested and later charged with trespass on a protected site and criminal damage.

Dennis, of Wembley, north-west London, will now appear at Westminster Magistrates' Court on Friday, police said.  

Responding to news of the break-in, Mr Wharfe said today: 'It took seven minutes to find this guy, which is a hell of a long time. Ten seconds is a long time, a minute is a long time.

'In 10 seconds you could run 50 yards, at the bottom end of the Palace that would take you into the front door of where the Queen lives, that's how accessible the Palace is from the perimeter wall at the bottom end.

'Once somebody is over that wall, unless you catch them immediately there's no telling where that person might go.'

He added: 'Where we sit today politically with international terrorism and our role in the world and where we sit with Isis, any publicity like this is suddenly spread by Twitter and by the internet and anything is possible.

'We have to be serious about it, the country is at a very high stage of alert.

'An attack on the Palace by one of the terrorist groups will engender tremendous publicity so you cannot rule it out, of course you can't.

'Anything can happen, something happened here yesterday and thankfully it wasn't a terrorist attack... but the point is it happened and it will cause alarm for the police.' 

Ken Wharfe, a former police guard for Princess Diana (right) and Princes William and Harry, has criticised royal security officers for the seven minutes it took them to catch an intruder at Buckingham Palace

The Queen chats with guests during the party at Buckingham Palace today, less than 24 hours after the breach

The Queen looked splendid in a mint green and lilac ensemble as she attended the party with Prince Philip

Despite the security breach, the Queen - resplendent in a mint green one-button coat and a cerise dress by Karl Ludwig Couture with a matching hat by Philip Sommerville – appeared in good spirits today.

She was attending her first garden party since she was caught on camera last week commenting scathingly about the behaviour of the Chinese delegation at last year's State Visit.

Some 8,000 people, many outstanding members of communities and charities, thronged the palace gardens drinking tea and iced coffee and eating delicacies such as cucumber and mint sandwiches and Eton Mess tarts.

Also accompanying the Queen were Prince Charles and the Duchess of Cornwall, Princess Anne, the Duke of Kent and Prince and Princess Michael of Kent.

Speaking earlier about the intruder incident at the Palace, Commander Adrian Usher, head of the Met's Royalty and Specialist Protection, said: 'I am content that our security measures worked effectively on this occasion and at no time was any individual at risk.'

A Buckingham Palace spokesman added: 'The Royal Household never comment on security matters, which are a matter for the Metropolitan Police. '

A man has been arrested after scaling a wall at Buckingham Palace yesterday evening. File photo

It is understood the Queen and Prince Philip were at the Palace at the time. They attended the State Opening of Parliament yesterday

The Met Police confirmed officers were called to the Palace grounds after the man scaled a wall.

A spokesman said: 'A man has been arrested following a security breach at Buckingham Palace.

'At 20:37hrs on Wednesday, 18 May, officers at the Palace were alerted after a 41-year-old man scaled an outside perimeter wall.

'He was located in the grounds by officers and arrested on suspicion of trespassing on a protected site contrary to section 128 of the Serious Organised Crime and Police Act 2005 seven minutes after the alarm was activated. The man remains in custody.

'The man was not armed. Taser was not deployed by officers. '

The palace wall is topped with razor wire but a number of intruders have managed to get in over the years

Several intruders have attempted to enter the Queen's London residence over the years.

In 1982, Michael Fagan managed to sneak into the monarch's private bedroom while she was still in bed.

He wandered around the Palace unhindered before waking the Queen, who spoke to him before fetching help.

Mr Fagan, who was later put into a psychiatric institution, set off two alarms but police at the building thought they were broken.

In 2013, Prince Andrew was left furious after he was confronted by armed police who mistook him for an intruder in the Palace grounds. Police later issued an apology to the Duke of York. 

A HISTORY OF BREACHES AT BRITAIN'S MOST ICONIC BUILDING: HOW THE PALACE BECAME A MAGNET FOR PROTESTERS AND ACTIVISTS

In 1982, Michael Fagan got into the Palace and woke the Queen in her bedroom

1982 - Michael Fagan evaded guards to get inside the Queen's private chambers while she was still in bed in 1982. The unemployed father of four, 31, spent around 10 minutes talking to the Queen after he climbed over the palace walls and up a drainpipe. The Queen managed to raise the alarm when Fagan asked for a cigarette, allowing her to call for a footman who held him until police arrived.

July 1992 - Kevin McMahon, 25, was arrested inside the grounds for the second time in a week. During his first sortie, he forced a helicopter carrying the Queen and the Duke of Edinburgh to divert as he roamed the grounds.

1994 - A naked paraglider landed on the roof of Buckingham Palace. American James Miller was fined £200 and deported.

1995 - Student John Gillard rammed the Palace gates in his car at 50mph, tearing one off its hinges.

November 2003 - Daily Mirror journalist Ryan Parry sparked a major alert when he managed to become a footman using false references and infiltrated the workings of the Queen's London home in November 2003. 

Parry claimed he was given the chance to get close enough to the Queen to have poisoned her and said no rigorous checks were made into his background. He took pictures of the bed in which US president George Bush and his wife Laura were to sleep during a subsequent state visit.

2012 - Four climate change activists were arrested in 2012 for scaling the Palace gates and chaining themselves to the railings. Two of them held a banner carrying a quote from the Prince of Wales reading: 'The doomsday clock of climate change is ticking ever faster towards midnight. We are simply not reacting quickly enough.'

September 2013 - A man scaled a fence at the Palace and was found in a room that had been open to the public during the day. Another man was arrested outside the Palace. Less than 48 hours after the incident, two police officers confronted the Duke of York in the Palace gardens demanding to know who he was.

A member of the 'Fathers 4 Justice' group stood on the balcony dressed as Batman in 2004

2013 - A man with a 6in kitchen knife was rugby-tackled to the ground by police outside the Palace after he jumped over a vehicle barrier in an attempt to see the Queen. David Belmar admitted trespass and possession of a bladed article. The court heard that he wanted to see the Queen because he was unhappy with his benefits.

November 2015 - Activists climbed on the roof of Buckingham Palace in a protest over fathers' rights in November last year. Martin Matthews, 48, and Bobby Smith, 33, used a ladder to breach security after another campaigner caused distraction outside the Palace.

2016 - A musical group claimed to have 'gatecrashed' Buckingham Palace, fooling guests at a private art talk last month. In a video uploaded online, Cat's Eyes said they had previously attempted to get into the Palace to perform a song from their new album. The group said they pretended to be a Renaissance ensemble performing music from that era, when really they gave a live rendition of their own song, We'll be Waiting.