(Reuters) - Tunisian authorities have arrested more than 20 suspected militants following the Bardo museum attack when gunmen killed foreign tourists, leading to a nationwide security crackdown.
Hundreds of Tunisians gathered for a mass in the cathedral in Tunis on Saturday, lighting candles to remember the victims - 20 foreign tourists and three Tunisians - in a ceremony attended by government ministers. Outside, there was a heavy police presence along the capital's central Habib Bourguiba boulevard.
Wednesday's assault - the most deadly attack involving foreigners in Tunisia since a 2002 suicide bombing in Djerba - came at a fragile moment for a country just emerging to full democracy after its pioneering popular uprising four years ago.
The government said the two gunmen had trained in jihadi camps in Libya before the attack at the museum inside the heavily secured Tunisian parliament compound. Japanese, French, Polish, and Colombian visitors were among the victims.
Authorities have arrested more than 20 suspected militants, including 10 believed to be directly involved in the Bardo attack, Interior Ministry spokesman Mohamed Ali Aroui said on Saturday. "There is a large-scale campaign against the extremists," he said.
The government plans to deploy the army to major cities to increase security following the shootings.
Islamic State militants have claimed responsibility for the attack, but social media accounts tied to an Al Qaeda-affiliated group in Tunisia have also published details purportedly about the operation.
Whoever was responsible, the Bardo attack illustrates how Islamist militants are turning their attention to North Africa, especially in neighboring Libya where two rival governments battle for control allowing Islamic State to gain a foothold.
The United States is increasingly worried about the growing presence of Islamic State militants in Libya.
U.S. officials said that because of its strategic position, Libya has become a springboard for would-be fighters from across North Africa wanting to link up with Islamic State. They could travel from there to Syria for frontline experience.
Four years after a popular revolt toppled autocrat Zine El-Abidine Ben Ali, Tunisia has completed its transition to democracy with free elections, a new constitution and compromise politics between secular and Islamist parties.
The country is heavily reliant on foreign tourists to its beach resorts and desert treks.
(Writing by Patrick Markey; Editing by Pravin Char)