The bomber, named as Abu Abdullah al-Britani, was said to have caused the blast near the city of Samarra, around 78 miles north of the country's capital Baghdad.
He reportedly detonated a bomb in a car, targeting a group of police officers in the city's Al Mu'tasim district.
Samarra has been the scene of fierce fighting in recent days between Iraqi Security Forces and ISIS supporters. Militant bases nearby were the focus of US air strikes on Friday.
However, pro-ISIS sources were claiming that the part of the city where the bombing is said to have taken place was now under the control of the ISIS militants.
Reports of the blast, and of the district being under ISIS control have not been verified.
Other reports said that the source of the blast had been a car bomb and the targets had been police officers.
A British terrorists with the same name was reported as being killed in an airstrike in Syria last month and a number of IS fighters from the UK are believed to use the moniker.
Some 32 British nationals are known to have died fighting for ISIS forces in Iraq and Syria.
Reports of the blast came after at least nine people were killed after militants attacked a police station the village of al-Salman, around 60 miles away from Samarra.
The attack started at dawn with a suicide car bomber hitting the blast walls that surround the police station in the village, just outside the town of Tarmiyah, a police officer said. An assault by armed militants then followed.
The attack killed five police officers and four civilians, leaving 11 other people wounded.
The al-Salman attack came a day after a string of bombings targeting Shia areas around Baghdad killed ten people amid tight security measures to protect pilgrims heading to the holy city of Karbala to attend the religious commemoration known as Arbaeen.
The event, which draws hundreds of thousands of Shia pilgrims, marks the passing of 40 days after the anniversary of the seventh century martyrdom of the revered Shia saint Imam Hussein, the grandson of the Prophet Muhammad.