The FBI says it is treating Friday's deadly attack on a Florida navy base as a presumed terrorist attack.

The Saudi gunman - who was training at the Pensacola site - killed three sailors before he was shot dead.

The FBI is trying to determine if he had acted alone or had connections to a group.

BBC News reports other Saudi students had been questioned but not arrested.

They were reportedly confined to the base, co-operating with investigators.

The US Navy said the two sailors who died in the attack "showed exceptional heroism and bravery in the face of evil".

BBC