The US has announced a bounty of up to $20m (£13m) for any information leading to four key Islamic State (Isis) commanders.
Mounting pressure on the leaders of the group, the Obama administration has said the total reward could be worth $20m under the US State Department's Rewards for Justice Program.
The four senior IS figures are Abd al-Rahman Mustafa al-Qaduli ($7m), Abu Mohammed al-Adnani ($5m), Tarkhan Tayumurazovich Batirashvili ($5m), and Tariq Bin-al-Tahar Bin al Falih al-'Awni al-Harzi ($3m).
According to the details provided by the State Department, Qaduli is a senior IS commander operating in Iraq after joining the al-Qaeda in 2004. While Adnani has been described as an official IS spokesperson, the other two are thought to be leading the group's wing of suicide bombers in key regions.
The bounty announcement has come a day after the IS claimed responsibility for the attack on an art show conducted to showcase Mohammad cartoons, in Texas.
The Iraqi-based group said "two soldiers of the caliphate" were behind the attack for conducting the event organised by a group critical of Islam.
IS leader Abu Bakr al-Baghdadi has already been the subject of a $10m reward under the State Department's programme. Ayman al-Zawahiri, the al-Qaeda leader, tops the Rewards for Justice list with a $25m bounty on his head.