By Yolande Knell
BBC News, Cairo
The Brotherhood tasted success in 2005 polls
It is not easy to find the headquarters of Egypt's largest opposition movement. The unremarkable building overlooking the Nile in Manial in central Cairo has no sign.
Only a nod from the security guard when you ask "al-Ikhwan al-Muslimun?" reassures you that you have arrived at the office of the Muslim Brotherhood.
Nowadays the Islamist organisation - which is officially banned - has more reason than usual to keep a low profile.
In recent weeks the Egyptian government has stepped up its crackdown on members ahead of local elections on 8 April. More than 800 have been arrested.
"It looks like the ruling National Democratic Party is not able to compete fairly with the Muslim Brotherhood," the Brotherhood's Deputy Chairman, Mohammed Habib, tells me. "Therefore it is resorting to odd and exceptional measures."
In 2005, Brotherhood candidates - running as independents - clinched more than a fifth of seats in Egypt's parliamentary elections. Mr Habib says the government wants to prevent a repetition of that success.
"They felt scared and panicked when they saw the result. Afterwards they changed their strategy and tried to marginalise and undermine the Muslim Brotherhood."
In spite of the serious topic of discussion, Mr Habib smiles often as I sit in his brightly-coloured office with a cup of hot sweet tea.
He gives a matter-of-fact account of how dozens of potential Brotherhood candidates were arrested.
Others were barred from entering registration offices or had their applications rejected by officials. When local courts upheld their complaints no action was taken.
"We have got used to it," he says. "It has become a routine that the ruling party acts like this."
Originally the Brotherhood hoped to field 10,000 candidates in the local elections. However, just 21 members have made it onto ballot papers.
Mr Habib takes the long view. "The authorities have cracked down on the Brotherhood many times before," he says - reflecting on its 80-year history - "but every time we come back stronger."
In her plush apartment on the outskirts of Cairo, the acting editor of the Muslim Brotherhood's English website, IkhwanWeb, is less composed. She realises as she tries to show me the site that access has been blocked.
"We believe the government has had a hand in closing down the website more than once this week," she says as she telephones for technical help.
Brotherhood leaders deny links with violence or sedition
Mariam Ali - not her real name - is an articulate university graduate. She is filling in for Khaled Hamza who was arrested outside his home in February.
"He is one of the moderates of the Muslim Brotherhood," she says. "We believe he was detained to try to silence the media's voice."
Hamza is not the only media worker to have been targeted. There have been attempts to arrest the editor of the group's Arabic website and the chairman's media advisor has been imprisoned.
"This is the first time the government has targeted our new media outlets," says Asem Shalaby, a publisher and Brotherhood leader. "This is how we communicate with people in Egypt and the outside world."
"The media campaign has become much more important than the electoral campaign as we know we are never going to win the elections."
Mariam admits her family fears for her safety but says she takes security precautions - such as working from home and keeping her identity a secret. She says her job is important.
"The West has a lot of misconceptions, such as linking the Muslim Brotherhood to violence or believing that we are a Machiavellian movement which is trying to turn Egypt into a caliphate [Islamic state] or dictatorship."
"We are trying to correct all these misconceptions."
There has been strong international condemnation of the latest round-up of Muslim Brotherhood members.
Last month the White House expressed its concern. The New York-based group Human Rights Watch called the action "shameless" and said it cast serious doubt on the election's legitimacy.
It also criticised the ongoing military trial of 40 senior Brotherhood members - charged with belonging to a banned group and possessing anti-government literature.
In Egypt though, some support the government's tough line.
"The Muslim Brotherhood is a challenge to the civic state of Egypt," comments Abdel Moneim Said, head of the al-Ahram Centre for Political and Strategic Studies.
"It is an illegal organisation which wants to establish a religious state in Egypt. It is not part of the democratic game."
Back in his office, Mr Habib waves a red fly swat as if brushing away such claims.
"We are strongly represented as a political party across Egypt," he says.
"We have declared our acceptance of democracy. Real democracy is dependant on political pluralism and the people's right to choose their leaders."
"We have faith in ordinary Egyptians because they want reform."