Abu Abdullah al-Britani, a British jihadi died along with dozens of others after detonating a suicide car bomb near the city of Samarra, 78 miles north of Baghdad, the capital of Iraq.
The suicide bomber, who was targeting police officers, died on the spot taking with him 'dozens' of people.
The gruesome incident was said to have been staged in Samarra's Al Mu'tasim district where a police gathering took place.
Samarra has seen heavy fighting recently between ISIS supporters and the Iraqi Security Force. Nearby militant bases were subjected to US air strikes last Friday.
The Al-Battar Media Foundation which is known to some as pro-ISIS tweeted: "Dozens of apostates killed in the operation of Abu Abdullah al-Britani in al-Mu'tasim area near #Samarra#IS #ISIS."
Pro-ISIS sources claim that the gruesome site of the incident is now under control by Islamic militants. However, reports of the incident, or of the district being controlled by ISIS, are yet to be verified.
Charlie Winter, a Middle East researcher at the Quilliam Foundation, also tweeted: '#Iraq: Another Briton dies in #IS VBIED op - Abu Abdullah al-Britani targeted a police gathering near #Samarra.'
In another report, a British jihadi using the name Abu Abdullah al-Britani was killed during an airstrike in Syria the previous month. The name is believed to have been used by many IS fighters coming from the UK.
It is said that around 32 British nationals were known to have fought for IS forces both in Syria and Iraq.