An American-Dutch Islam convert, said to be part of the former Hofstad group terrorist network, has been killed in Syria or Iraq, Dutch media report on Thursday.

The Hofstad group is the name police gave to a group of young Muslim men in The Hague. Their number is said to have included Mohammed Bouyeri who murdered film maker Theo van Gogh in 2004.

Jermaine W’s brother Jason published the news of his death on his Facebook page, shock blog GeenStijl says.

Jason and Jermaine, who have an American father and Dutch mother, were both Muslim converts. Jason, who served eight years in jail for throwing a hand grenade at police, has since renounced Islam.

Jermaine W was found not guilty of being a member of a terrorist group in 2006. He is thought to have gone to Syria or Iraq in September last year with his wife and children.