An Italian prosecutor said Tuesday that Youssef Zaghba, the third man who carried out last weekend's deadly attack in London, was notified to Britain as a "possible suspect" back in March 2016.

Bologna prosecutor Giuseppe Amato said the warning had been transmitted after Zaghba was intercepted at the city's airport trying to board a plane for Turkey, en route for Syria. British police had earlier said the 22-year-old had not been on their radar prior to Saturday's attack.