A Belgian woman who converted to Islam after marrying a radical Muslim carried out a suicide attack in Baghdad earlier this month, say Belgian prosecutors.
Other European extremists are known to have travelled to Iraq to fight the US-led forces, but she is believed to be the first female European bomber.
On Wednesday, police raided the homes of people thought to have links with the woman, who has not been named.
At least one person was detained in the raids in Brussels and Antwerp.
Spokeswoman Lieve Pellens confirmed that a Belgian-born woman had carried out an attack in Baghdad on 9 November.
She is believed to have been born in Belgium and converted to Islam after marrying a Muslim radical.
The De Standaard newspaper said the woman’s Belgian passport was found on her body after the attack on a US military convoy. She is reported to be the only victim of the attack.
Earlier this year, French Interior Minister Nicolas Sarkozy said at least seven people from France have been killed in Iraq and elsewhere fighting for al-Qaeda.
Belgian authorities have also had to deal with other cases of Belgian-based Islamic extremism. Thirteen men are currently on trial accused of membership of a militant group that has been linked to bombings in Madrid and Casablanca.
Defence lawyers say the only evidence against some of them is that they knew men charged with serious crimes.
The men are accused of belonging to the Moroccan Islamic Combatant Group (GICM), accused by the US of aiming to establish an Islamic state in Morocco and supporting al-Qaeda’s jihad against the West.