Updated

Syrian state TV is reporting that government forces have launched a new operation targeting underground tunnels used by the Islamic State group in the capital, Damascus.

The TV says the aim of the operation is to destroy dug-out trenches and tunnels in the Hajar al-Aswad neighborhood and the nearby Palestinian refugee camp of Yarmouk that is also mostly controlled by IS.

A group of journalists taken on Tuesday to the adjacent neighborhood of Qadam witnessed intense shelling and airstrikes on IS positons in the camp and Hajar al-Aswad.

The area in southern Damascus is the last part of the capital not controlled by President Bashar Assad's forces. Other insurgents in the area, including an al-Qaida-linked group, have said they would relocate to rebel-held regions in northern Syria.