A senior aide of Islamic State (IS) leader Abu Bakr al-Baghdadi has reportedly been killed in an airstrike in Iraq.

"Iraqi warplanes carried out a security operation today, resulting in the killing of...Abu Hajar al-Suri," General Babaker Zebari said.

The attacks in Nineveh province were "based on accurate intelligence information" and the target was destroyed, the army officer added.

Suri's death has not been independently confirmed, which could be difficult as the strikes were in an area, between the second city of Mosul and Tal Afar, outside government control.

Two other senior members of the jihadist movement were also killed - an explosives operative and the military leader of Tal Afar - according to reports.

IS-led militants launched a major offensive in June, taking over Mosul and then sweeping through much of the country's Sunni Arab heartland in the north.

The group also holds significant territory in neighbouring Syria, and has declared a cross-border Islamic "caliphate" in which it has carried out several atrocities.

IS, also known as ISIS and ISIL, has beheaded two American hostages - journalists James Foley and Steven Sotloff - and has threatened to take the life of British captive David Haines.

The group said the killings were in retaliation for US airstrikes against IS targets in Iraq. The strikes have helped Iraqi and Kurdish forces retake the important Mosul Dam, which controls much of the country's water supplies.

A months-long IS siege of the town of Amerli, where thousands of residents had been trapped by the jihadists, has also been broken.