A tense atmosphere permeated Al-Hussein Mosque in Old Cairo ahead of the religious Ashoura celebrations expected on Thursday night.

Egypt's Ministry of Awqaf (religious endowments) closed the shrine at the heart of Al-Hussein Mosque to visitors for the second consecutive day to avert possible clashes between Salafists and Shias during the Ashoura commemorations.

Ashoura, the 10th day of the Islamic calendar, is a festival for the general Muslim community who celebrate it for a number of religious events that, although unrelated, coincided on the same day. 

Shia Muslims, however, commemorate on Ashoura the martyrdom of Prophet Mohamed's grandson, Imam Al-Hussein, whose decapitated head is believed to be buried at Old Cairo's Al-Hussein Mosque.

Security forces formed a cordon around the Al-Hussein Mosque early Thursday morning to prevent any possible friction between the two groups.

Egyptian newspapers and TV shows had announced earlier this week that Egyptian Shias, led by their prominent activist Ahmed Rassam El-Nafis, planned to commemorate Ashoura at Al-Hussein Mosque.

El-Nafis denied any such plans, asking "How can I organise such a big event when I have just returned to Egypt on Wednesday?"

Speaking to Ahram Online from his home in Mansoura, he angrily added, "I announced that I did not plan for anything but the media in Egypt is insisting on inserting my name in such false news."

Shia activist Taher El-Hashimi stated to Ahram Online that Egyptian Shias were only planning to visit the mosque and denied any plans for special commemorative observances, wondering, "How can we do it when the mosque is under the supervision of the Ministry of Awqaf?" 

The Ministry of Awqaf controls mosques in Egypt according to Sunni doctrines and does not recognise Shia mosques or rituals.

As Salafist groups – whose doctrine prohibits the sanctification of persons and shrines – have warned they would not allow any Shia commemorations at Al-Hussein Mosque, Sufi orders announced their intent to protect the shrine and mosque dedicated to the Prophet's grandson from potential Salafist attack, should the Shia hold celebrations there. 

Over the past two years Sufi orders – whose doctrine venerates Muslim saints, many of whom are descendants of Prophet Mohamed – have accused Egyptian Salafist groups of standing behind attacks against the shrines of Muslim saints.

In June 2013 four Egyptian Shias, including influential Shia sheikh Hassan Shehata, were brutally killed by an angry mob in a Giza village following anti-Shia incitement by Salafist preachers.