There were unconfirmed reports that tourists from several European countries had been taken hostage.

The BBC reports that the shooting happened at the Bardo Museum, which is next to the parliament building in central Tunis.

At the time of the attack deputies were discussing anti-terrorism legislation. Parliament has now been evacuated.

An interior ministry spokesman told Reuters that two militants were holed up inside the museum, surrounded by security forces.

The museum, renowned for its collection of antiquities, is a major tourist attraction in Tunis.

Concerns about security in Tunisia have increased as neighbouring Libya has become increasingly unstable.