Hundreds of police officers in Algeria have sealed off avenues in the capital to prevent an opposition demonstration against plans to drill for shale gas in the south of the country.
A few dozen opposition activists were able to briefly demonstrate near the rally site in Algiers before being arrested.
Instead, the government sponsored folkloric dancers in the center of the city.
Tuesday marks the 44th anniversary of the nationalization of the oil industry and an opposition coalition had hoped to use the occasion to protest the negative environmental effects of exploitation plentiful shale gas reserves.
There have been protests for the last six weeks, but demonstrations are illegal in the capital.
Algeria relies almost entirely on its oil but shrinking reserves and dropping prices have threatened the economy.