Sudanese police have fired tear gas at stone-throwing protesters who are angry at the lack of democratic reform before a forthcoming referendum and election.
Unconfirmed reports say dozens of protesters were arrested during the clashes, in the city of Omdurman. The violence came a day after leaders agreed rules for the election and a referendum in which the south will decide whether to secede.
A two-decade civil war between the north and south ended in 2005. Both sides agreed to the referendum and election as part of the peace deal that ended the war.
But southern leaders have expressed fears that supporters of President Omar al-Bashir would try to sabotage the votes and ensure the south would not get independence.
The BBC's James Copnall in Omdurman says hundreds of demonstrators gathered at the headquarters of one of the parties organising the rally, intending to march to parliament.
They chanted slogans about freedom and justice, but riot police stopped them about 100m up the road firing tear gas, our correspondent says.
<<Print>>