In Syria, three people have been killed in an explosion in a crowded bus carrying Iranian pilgrims in the capital Damascus. <br/><br/>The blast occurred at a petrol station near the Sayyida Zeinab shrine for Shia Muslims. The Syrian interior minister said it was not a terrorist act but a burst tyre had caused the blast. <br/><br/>However, an earlier report suggested a gas bottle carried by the pilgrims in their luggage had exploded.<br/>