MP Chloe Smith has hit out at a 'disruptive and distressing' white powder hoax at her constituency office in Norwich.

Police and paramedics sped to Vulcan Road on Friday after her parliamentary assistant received a brown envelope containing a white substance, which later turned out to be a harmless protein powder.

The Norwich North representative is one of two MPs who received suspect packages at their offices.

Parliament's Serjeant at Arms has now issued advice to other politicians about how to deal with such attacks and warned politicians to be on the lookout. Ms Smith, who was not at the office in Norwich when the letter arrived, condemned the hoax, saying it was her employees who were the ones affected by such attacks.

She said: 'It is my staff who bear the brunt of this. It is not fair. As an MP you expect to be able to get on with your job of serving your constituents without coming under physical attack, which is what letters such as these are, even if they are hoaxes.

'It is not fair on the staff of MPs who help open the post to be attacked in this way.'

She praised Norfolk Police for their professionalism and quick actions.

'They may even stand out across the country as an example of good action, having heard that this has happened to other MPs as well,' she said.

Her parliamentary assistant of three years, Alice Saunders-Eaves, said she had not thought anything of the handwritten envelope written in black biro when she picked up the post on Friday as the office often received letters from constituents written by hand.

The powder was hidden in what looked like a folded up piece of notepaper.

The 27-year-old said: 'I got white powder all over my desk and hands and trousers.

'I had a brief look to see if there was anything written on the paper and also saw there was a postmark from Exeter.'

She said that luckily all of the Norfolk MPs and their office staff had been offered training in how to deal with violence and suspect packages by the police at its Wymondham headquarters in the spring.

Mrs Saunders-Eaves, a former UEA student, said that police arrived very quickly but were not able to enter the building because they had to wait for a specialist unit to arrive from Suffolk.

'They kept ringing me to see if I was feeling okay and asked questions about the letter,' she added.

'I was advised not to eat or drink or visit the bathroom. It was uncomfortable.

'I thought it was probably nothing. They told us that 99pc of the time it's a hoax, so I wasn't frightened in that respect. But I did feel nervous at times.'

She said: 'I couldn't help but think of how it was wasting the time of the police and trained professionals. I felt bad from that point of view.'

Politicians and other organisations have been on guard since five people were killed in the US after news organisations and senators were sent highly purified anthrax spores in 2001.

In 2002, a former chemistry teacher was jailed for two years after sending hoax anthrax mail to the Welsh first minister Rhodri Morgan at the height of the US anthrax scare.

A Norfolk police spokesman said: 'Officers were called to a property in Vulcan Road North, Norwich, shortly before 11am on Friday, August 23, following reports of a suspicious package.

'The package has been examined and the contents analysed and not deemed to be harmful. At no stage was there any threat to the surrounding community. However, investigations are ongoing to identify the sender.'

In an email to MPs, Richard Latham, deputy Serjeant at Arms said: 'Members and their staff should be aware that there have been recent incidents of brown envelopes containing white powders being received in members' offices. Following analysis these powders were confirmed as harmless.'