Extra security measures have been introduced at the headquarters of Norfolk County Council, after an intruder filmed himself and his dog wandering through the offices at County Hall.

It means groups of 20 or more who organise events at County Hall in the evenings or weekends will be charged for a dedicated security officer, while an electronic tracking and security monitoring system is to be introduced.

Four videos were posted on YouTube earlier this year showing a man and his pet spending at least an hour walking through the Martineau Lane building.

According to the man's own voiceover, he was in the building when it was closed on a Saturday.

The man smokes and drinks, turned on a computer and a radio, looked at documents on desks and at one point, bumped into a county council worker, who did not challenge him.

In the council's legal department NPLaw, he read documents and case papers he found on desks and went into the office of head of law Victoria McNeill, where he rummaged around her desk.

The man started filming on the top floor of the Martineau Lane building and continues all the way down to the basement, but he did not state how he got into the building. He also did not show how he got out.

A Norwich man had been charged with racially aggravated harassment following the incident at County Hall and was due to appear before magistrates last month. But the case was discontinued.

In the meantime, questions over security were raised, with two asked by member of the public Alan Hall at a council meeting this week.

He asked what improvements to security had been made and what steps had been taken to ensure the offices at NPLaw were locked when not attended.

Cliff Jordan, cabinet member for efficiency, said: 'Norse undertook a full site survey as part of the security review following the incident and identified a number of improvements to the security arrangements at County Hall.'

That means groups of more than 20 external delegates hiring rooms at County Hall at weekends or evenings will be charged for the services of a security officer who will be responsible for making sure the building is secure while allowing the meeting to take place.

Mr Jordan added: 'An electronic tracking and security monitoring system to the County Hall complex will be installed. It will allow the movements of the security staff to be audited, ensuring good security coverage on a 24/7 basis.'

An audit of swipe cards held by staff is being undertaken and, on the NPLaw issue, Mr Jordan said: 'NPLaw's offices are, for the most part, open plan and Norse has looked at options for making them more secure.

'In the meantime, steps have been taken to ensure that confidential material is all stored away in locked cabinet when not in use.'

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