Around 20 people died and 106 were injured in the bomb attack on the Brussels metro Tuesday, local mayor Yvan Mayeur said.

"According to initial figures, there are around 20 dead with another 106 wounded, 17 of them gravely and another 23 seriously," Mayeur said, describing the scene at Maalbeek station as "very chaotic."

A twin bomb attack on Brussels airport claimed at least 11 lives, taking the combined death toll to around 31, according to provisional reports.