Students and trade unions are expected to be leading demands for democratic reform in the kingdom, ruled by King Mswati III, sub-Saharan Africa’s last absolute monarch.
The protests mark the anniversary of a Royal Proclamation in 1973 that banned all political parties and allowed the king to rule by decree.
Over the last year, protests have mushroomed amid deepening frustration in Swaziland's impoverished majority, who are living through a crippling financial crisis under a king rated by Forbes magazine as among the 15 richest monarchs in the world, the AFP news agency reported.
Demands for reform are expected to grow as Swaziland heads for elections next year.
Activists also want the government to scrap a new 14-percent value-added tax imposed last week.
Last year during similar protests, security forces violently dispersed marchers. Since then, more than 60 protests have rattled the country. They were often small but still a sea change in a kingdom that tolerates little dissent, AFP reported.
The government is tightening the screws. Last week it deregistered the Trade Union Congress of Swaziland (TUCOSWA), a new federation of labour that has called for a boycott of next year’s elections and has taken a lead role in organising this week’s protest.
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