A mosque in the centre of Libya's capital containing Sufi Muslim graves was bulldozed in broad daylight, in what appeared to be the country's most blatant sectarian attack since the overthrow of Muammar Gaddafi.
Government officials condemned Saturday's demolition of the large Sha'ab mosque and blamed an armed group who, they said, considered graves and shrines to Sufi figures un-Islamic.
It was the second razing of a Sufi site in two days. Ultraconservative Islamists wrecked shrines with bombs and a bulldozer and set fire to a mosque library in the city of Zlitan in the early hours of Friday, an official said.
Libya's rulers have struggled to control armed groups who are competing for power in the North African country a year after Gaddafi's fall. Dr Mohamed al-Magariaf, president of the newly elected National Congress, called the prime minister to an emergency meeting yesterday.
"What is truly regrettable and suspicious is that some of those who took part in these destruction activities are supposed to be of the security forces and from the revolutionaries," he said.
Interior Minister Fawzi Abdelali resigned yesterday after coming under fire for the performance of the security forces, an official from his office said.
"He submitted his resignation to protest against congressmen criticising the government and to defend the revolutionaries," the official said, referring to former rebels who now form part of Libya's security services.
The bulldozer levelled the mosque, surrounded by police, who prevented people from approaching and did not stop the demolition.
A government official said that authorities tried to stop the demolition, but after a small clash decided to seal off the area to prevent any spread of violence.
A man who appeared to be overseeing the demolition said the Interior Ministry authorised it after discovering people had been worshipping the graves and practising "black magic".
One of Libya's highest-profile cultural clashes has been between followers of the mystical Sufi tradition and Salafis, who say Islam should return to the simple ways followed by its Prophet.