Tunisia, the birthplace of the “Arab Spring” uprisings, will vote next week in a landmark election that now risks being overshadowed by growing tensions between hard-liners and secularists over the country’s future direction.

The protest started peacefully, with more than 10,000 people shouting “Allahu Akbar!” or “God is greatest!” and demanding the imposition of Islamic law in Tunisia. It was the biggest protest to date by hard-liners in the capital.

When the crowd approached the Casbah, where caretaker Prime Minister Beji Caid Sebsi has his office, some groups tried to break through police lines.

Riot police fired tear gas and moved in with their batons to try to disperse the crowd. The protesters responded by throwing stones at police.

After about half an hour, most of the crowd dispersed leaving only a few hundred young men who were still throwing missiles at police.

Witnesses told Reuters there were separate protests by hard-liners in three other locations around the capital, each with several thousand people taking part.

The witnesses said group was on the Mohamed V boulevard, just north of the city center, and was trying to reach the offices of a television station that angered religious conservatives by broadcasting a film that depicted Allah.

Tunisia electrified the Arab world in January when mass protests overthrew president Zine El-Abidine Ben Ali. Its revolution inspired uprisings in Egypt, Libya and Yemen that have reshaped the political landscape of the Middle East.

The North African country will vote on Oct. 23 for an assembly which will draft a new constitution. The vote is set to be Tunisia’s first genuinely democratic election.

But the vote has helped fuel tension between Islamists who are free for the first time to express their faith and secularists who believe their modern, liberal values are under threat.

Hard-liners clashed with police last week in a suburb of Tunis after the broadcast of a controversial film.