The Russian Navy on Thursday fired seven cruise missiles at Islamic state targets in the suburbs of Syria's Deir al-Zor, the Russian Defence Ministry said in a statement on Thursday.

It said the missiles were fired from two submarines in the eastern Mediterranean from a distance of 500-670 kilometres (727 miles).

"The targets were command posts, communication centres, as well as militants' weapons and ammunition stockpiles in areas of south-east Deir al-Zor under the control of Islamic State," the ministry said.