Italian news outlet La Repubblica TV has aired amateur video filmed by an Italian couple that were caught in the Bardo museum during last week's attack in the capital Tunis.
Marcello and Maria Rita Salvatori were filming their tour of the museum when the sound of gunfire was heard.
Several tourists can be seen visibly jumping in surprise.
Without switching off the camera, the couple caught the ensuing flight of the panicked tourists as they ran from corridor to corridor trying to escape the attackers.
Gunmen killed 20 foreign tourists, including Japanese, Polish, Italian and Spanish visitors, on 18 March, as they got off buses at the Bardo Museum, inside the parliament compound that is normally heavily guarded.
It was the worst attack in more than a decade in Tunisia, testing the North African country's young democracy four years after the revolt that overthrew autocrat Zine El-Abidine Ben Ali and opened the way for free elections.
The Bardo museum was expected to re-open on Tuesday but suspected security fears appear to have delayed the opening until this weekend.
