A Tunisian Salafist leader on Monday escaped from a mosque that had been surrounded by security forces seeking to arrest him over clashes at the US embassy last week, a Reuters witness said.

Saif-Allah Benahssine, leader of the Tunisian branch of the hardline Islamist Ansar al-Sharia, slipped away after hundreds of his followers stormed out of al-Fatah mosque in Tunis, some of them wielding sticks and creating panic among pedestrians.

A few minutes earlier, around 1,000 riot and anti-terrorist police forces had retreated by some 200 metres (660 feet) from the mosque for unexplained reasons, witnesses said. Interior Ministry officials could not be reached for comment.