Tunisian TV has shown surveillance video from the day of the deadly museum attack at the national museum in Tunis that left nearly two dozen foreign tourists dead. Three Tunisians also died.

The grainy video appears to show three armed gunmen walking through empty halls of the Bardo museum on  Wednesday.

The video also includes what appear to be still images of two of the gunmen after they were gunned down by security forces.

The 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 a popular uprising four years ago.

Authorities have arrested more than 20 suspected militants, including 10 believed to be directly involved in the Bardo attack, according to the interior ministry.