Sudanese security authorities confiscated the Sunday edition of the independent newspaper Al Khartoum because it reported on an opposition protest, a source at the newspaper said.
On Saturday, police used teargas and batons to break up a protest by opposition party members calling for the release of politicians and activists who were detained after attending a meeting with armed rebel groups in Kampala this year.
A source at Al Khartoum said security agents seized the Sunday edition of the paper carrying a report on the protest, something which local newspapers would not usually do.
"The reason goes back to the paper's coverage of the demonstration staged by opposition members to demand the release of political prisoners yesterday," the source said, asking not to be named for security reasons.
There was no immediate comment from the security agency. The National Press Council, which is in charge of licensing newspapers, could not be immediately reached for comment.
Sudan's constitution guarantees press freedoms, but journalists complain they face heavy pressure from authorities, especially after the secession of South Sudan in 2011.
While the Arab-African country has avoided the mass unrest that unseated rulers in neighbouring Egypt and Libya, small demonstrations have broken out over rising prices.