The breach resulted in the Humberto Delgado Airport being shut down for 34 minutes, with some flights diverted to Porto and Faro.

The Home Minister said last night that the four Algerians were not connected to any terror groups and were merely trying to enter the European Union while in transit to Cape Verde.

Minister Constança Urbano also said she was satisfied with the conduct of airport officials, and a full inquiry had been launched.