Five people have been killed and at least 45 have been left injured, some in critical condition, after a gunman went on a shooting spree at Fort Lauderdale airport on Friday. Police have arrested the suspect who they have identified as 26-year old Esteban Santiago.

Santiago is an Army National Guard veteran who once served in Iraq and was given an honourable discharge last August. According to the suspect's brother, Esteban had recently been receiving psychological treatment.

Officials said that the suspect was a passenger on a Delta Airline flight from Anchorage via Minneapolis, and brought with him a checked gun which was his only piece of luggage. He was said to have loaded the weapon in a bathroom before opening fire on everyone in the baggage claim area of terminal 2.

His shooting spree left five people dead and 8 people wounded, but a total of 37 other people suffered minor injuries as a result of the attack, including diabetic related issues and panic attacks, according to the Broward Sheriff's office. Florida governor Rick Scott condemned the shooting and called it an "evil, despicable act." He also called for prayers for the victims in the hospital.

Per CNN, the 26-year old Santiago works as a security guard in Alaska. Alaska is also where he served his final military assignment before being honourably discharged. Santiago was a member of the Alaska Army National Guard from November 2014 up until August of last year. According to a spokeswoman for the National Guard, Esteban was discharged due to unsatisfactory performance.

According to NBC News, the suspect had laid down on the ground "spread-eagle" style for at least 10 to 15 minutes before being arrested by police. Both family and federal sources claim that Santiago had been suffering from mental health issues. Authorities are still unsure what Santiago's motive was for the shooting, but the FBI has not ruled out "terrorism" as one of them.