TUNIS (AFP)---The head of a Tunisian Salafist group wanted by the authorities over an attack on the US embassy delivered a sermon Monday in a Tunis mosque that was surrounded by police. 

Seif Allah Ibn Hussein, also known as Abu Iyadh, who heads the extremist Ansar al-Sharia movement, called during his speech for the resignation of Interior Minister Ali Latayedh, a member of the ruling Islamist party Ennahda.

The security forces deployed in force, but at a distance, around the building, because women and children were also present, a security source said.

Inside and outside the mosque, young hardline Islamists shouted "Allahu Akbar!" (God if greatest) and "Obama! Obama! we are also Osama!" in reference to the slain Al-Qaeda mastermind Osama bin Laden.

"We will never hand over Abu Iyadh," they shouted, while calling for jihad and threatening Jews with the slogan: "Mohammed's army is back!"

The atmosphere was tense around the mosque, located between two main arteries in the capital, and where a large number of those who took part in 

Friday's violent protest outside the US embassy set out from.

Four people were killed and dozens wounded during the demonstration by angry Muslims outside the US embassy that turned violent Friday, with protesters hurling petrol bombs and storming the mission, while police fired live rounds and tear gas.

Abu Iyadh escaped arrest on Friday when the police visited his house, shortly after the violence that took the security forces nearly three hours to bring under control, according to one of his supporters.

"The police came on Friday evening to the house of Abu Iyadh, but they didn't manage to arrest him because he wasn't there," he told AFP.