An Iraqi airport has been closed for a week following a suspected terrorist plot to hijack an airliner and fly it into a Shia shrine. Najaf airport remains closed after reports were received by officials that a group of insurgents planned to carry out the attack on the Imam Ali shrine which is located in the city of Najaf.

The shrine is one of the holiest Shia sites in Iraq. The flight paths of aircraft flying over Najaf have been altered as well as those for aircraft flying near the holy town of Karbala because it is an important destination for Shia Pilgrims.

Two men have been taken into custody following reports of the potential threat. One man is suspected of being the intended pilot for the aircraft and the other was a member of the ground crew at Najaf airport.

Abdul-Qader al-Obeidi, Iraq’s Defence Minister, said that details of the plot to hijack a plane were not yet clear, but that the authorities had to take the reports seriously. Last week, Bagdad Airport was also closed but was allowed to reopen soon afterwards.

Sunni insurgents are a constant threat to Shia holy sites. The Najaf shrine is said to be the resting place of Imam Ali who was the Prophet Muhammad’s cousin. In 2004, the shrine was the scene of clashes between the Shia Mehdi Army and US soldiers. Following Iraq’s 2005 elections, an attack by Sunnis on the Samara shrine led to an outbreak of violence which continued for two years.