Iran says it has killed the alleged mastermind of twin attacks last week claimed by the Islamic State group.

Islamic State (IS) militants have abducted 300 cement workers and contractors in an area north-east of Damascus, Syrian state TV reported as fighting elsewhere in the country also worsened.

Lebanon began limiting the flow of Syrians entering the country yesterday, placing unprecedented restrictions on their entry, as it struggles to cope with a flood of asylum seekers fleeing civil war.

An internet video has been released purporting to show the beheading of US reporter Steven Sotloff by the Islamic State group.