An Islamic State group rocket expert believed to have been involved in an attack that killed a US Marine has died in a drone strike in Iraq, a spokesman said Sunday.

Staff Sergeant Louis Cardin was killed last month by an IS rocket attack that also wounded eight Marines at an artillery position in the Makhmur area of northern Iraq.

"Several hours ago, we killed an ISIL (IS) member believed responsible for the rocket attack that resulted in the death of Sergeant Cardin," Colonel Steve Warren, the spokesman for the US-led operation against the jihadists, told journalists in Baghdad.

Jasim Khadijah "was an ISIL member and former Iraqi officer," he said.

He was "a rocket expert, apparently... he controlled those attacks," Warren said, adding that the strike also killed five other IS fighters and destroyed a drone and two vehicles.

IS overran large parts of Iraq in 2014, but the country's forces have since regained significant ground with the backing of US-led air strikes and training.

US President Barack Obama repeatedly pledged that there would be no "boots on the ground" to fight IS, but has deployed special forces to Iraq who are carrying out raids targeting the jihadists.

An American special operations soldier was killed last October during a joint raid with Kurdish forces against IS in Hawijah, a northern Iraqi town.

Syria's Qaeda spokesman, 20 jihadists dead in strikes: monitor
Beirut (AFP) April 3, 2016 - The spokesman for Al-Qaeda's Syrian affiliate, Al-Nusra Front, his son and 20 other jihadists were killed in air strikes Sunday in the northeast of the country, a monitor said.

"Abu Firas al-Suri, his son and at least 20 jihadists of Al-Nusra and Jund al-Aqsa and jihadists from Uzbekistan were killed in strikes on positions in Idlib province," Syrian Observatory for Human Rights chief Rami Abdel Rahman told AFP.

It was not immediately clear if the raids were carried out by Syrian regime warplanes or their Russian allies.

Abdel Rahman said Suri was meeting with other leading jihadists in Kafar Jales when the raids took place.

Two other Al-Nusra and Jund al-Aqsa targets were also hit and many were seriously injured, he added.

Syrian Suri, real name Radwan Nammous, fought against the Soviet forces in Afghanistan where he met Al-Qaeda leader Osama bin Laden and Abdullah Azzam, a bin Laden mentor, before returning to Syria in 2011, according to supporters on Twitter.

On Wednesday, a drone strike near IS's de facto Syrian capital Raqa killed a jihadist commander, according to the Observatory, the latest in a series of blows to the jihadists in recent weeks.

Idlib province has under the control of the Al-Nusra Front and its allies since 2015.

A temporary ceasefire between government forces and rebels has largely held since February 27, but it does not cover Al-Nusra Front and the Islamic State group.