TUNIS - The Tunisian government, citing concerns of possible violence, has banned a series of marches planned for Friday by hardline Islamists and rival groups amid rising religious tensions in a nation struggling to emerge from years of secular dictatorship.

The announcement Thursday by the Interior Ministry comes as Tunisians are reeling from clashes earlier this week between police and religious youth in the capital and other cities after protests erupted over an art exhibit that hardline Islamists said was blasphemous.

Tunisians overthrew secular dictator Zine El Abidine Ben Ali last year in a popular uprising that sparked similar movements around the region.

The old regime savagely repressed any manifestations of political Islam. In its absence there has been an upsurge of new religious groups.

The growing tensions in Tunisian society now are not just between the religious-minded and secularists, however, but also between moderate Muslims and ultraconservative Islamists.

Past attempts by the Interior Ministry to ban demonstrations by secular groups have resulted in clashes between police and protesters.

The artwork that spurred the latest clash included paintings caricaturing Mecca, portraying a nude woman, and showing the word “Allah’’ spelled with strings of ants.