LONDON — A local council chief in Britain say the two suspects arrested over last week’s London subway bombing are an 18-year-old refugee from Iraq and a 21-year old believed to be from Syria, both of whom were fostered by a British couple.

The 18-year-old was detained Saturday at the port of Dover.

The 21-year-old was held later the same day in Hounslow, west London.

Police are searching three addresses, including the suburban home of Penelope and Ronald Jones, who have served as foster parents for more than 200 children.

Local council chief Ian Harvey says he believes the 18-year-old is an Iraqi orphan who moved to the U.K. when he was 15. He says the 21-year-old was also a former foster child of the Joneses.

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