Tunisian Prime Minister Habib Essid has sacked the Tunis police chief and several others in the wake of a deadly museum attack last week that left 20 foreign tourists dead, his office announced Monday.

Essid fired six police chiefs in total, including those in charge of tourist security and an intelligence brigade, in the wake of the attack on the capital's Bardo museum.

"He visited [the area around the museum] last night and saw several deficiencies," Essid's communications director, Mofdi Mssedi, told AFP. "So he has decided to fire a number of officials, including the Tunis police chief and the police chief for the Bardo [area]."

It was the worst attack in more than a decade in Tunisia, testing the North African country’s nascent democracy four years after the revolt that overthrew autocrat Zine El-Abidine Ben Ali.

Two gunmen were shot dead at the scene and authorities have so far arrested more than 20 people, 10 of whom officials believe were directly involved in the attack. Some had recently returned from fighting for Islamist militant groups in Syria, Iraq and Libya.

Islamic State group militants claimed responsibility for the attack although a local al Qaeda-affiliated group known as Okba Ibn Nafaa has also published details and comments on the assault.

Tunisia has been largely spared the violent aftermath of the Arab Spring uprisings of 2011, with secular and Islamist parties overcoming their divisions to compromise, approve a new constitution and hold free elections.

Hardline Islamist groups also emerged after the revolt against Ben Ali swept away his one-party rule. Since then security forces have been caught up in a growing battle with extremists, some of whom are returning from training and fighting overseas. More than 3,000 Tunisians are thought to have left to fight in Syria and Iraq.

Authorities say the two gunmen killed in the Bardo attack trained in jihadi camps in Libya.

(FRANCE 24 with AFP and REUTERS)