They have ordered everybody... to leave the house, and have assaulted one phtographer

Thulani Mthethwa

But the police issued a statement saying it could not go ahead because "such a conference will adversly affect the securirty of the country".

Thulani Mthethwa of the Guardian newspaper of Swaziland, who was at the press conference, spoke to BBC News Online after attending the news conference in the town of Manzini.

Price for freedom

"They have ordered everybody, local and regional journalists to leave the house, and have assaulted one photographer," he said.

The Swaziland Democratic Alliance includes civic groups, opposition parties, students and trade unionists.

Jan Sithole is a key pro-democracy activist

Alliance representative Jan Sithole said that protesters were prepared to pay any price for freedom.

Detained politician Mario Masuku, of the People's United Democratic Movement is facing charges of sedition and faces up to 20 years in jail.

Posters and graffiti

Mr Sithole said Mr Masuku had been detained because of the views he was expressing, which were not treasonous by international standards.

A year ago Mr Masuku had called on Swazis at a rally to "do away with the Mswati government" - referring to King Mswati III.

Posters of the detained politician pasted around the capital Mbabane were hurriedly removed on Friday.

King Mswati appears unyielding

But Mr Mthethwa says the security agents are finding it a little harder to get rid of a graffiti on a security wall which says: " Release Mario Masuku".

King Mswati is Africa's last absolute monarchy, and political activists have for some time now been trying to overturn the ban on political parties which has been in place since 1973.

The king recently abandoned parts of a controversial press decree following an international outcry.

But a constitutional review commission according to King Mswati, found that the people of Swaziland wanted to keep the absolute monarch as head of state and govenrment.

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