(Islamist demonstrators wave flags during a protest outside the Tunisian Parliament in Tunis March 16, 2012. Thousands of Islamists demand the inclusion of the Islamic Law in the constitution. The flag reads "There is no god but Allah and Mohammad is his prophet". REUTERS/Zoubeir Souissi)

Thousands of Tunisian Islamists took to the streets on Sunday to step up their demands for the creation of an Islamic state in one of the most secular Arab nations.

About 8,000 conservative Salafi Islamists filled the capital’s Habib Bourguiba Avenue, a focal point of the 2011 revolution that sparked uprisings across the Arab world.

Waving black flags, they shouted slogans demanding that Islamic law, or sharia, be defined as the main source of legislation in Tunisia’s new constitution.

“This is not a show of force, but they should know that we can mobilize hundreds of thousands on the streets if they refuse the application of sharia,” said a young man who gave his name as Abu Jihad.