Shooting suspect may be executed

Agents looking into motives for attack, including terrorism

US authorities have charged the Iraq war vet accused of shooting five people dead and wounding six at a Florida airport with federal crimes that could carry the death penalty.

The Justice Department on Saturday charged Esteban Santiago, 26, with firearms offenses and carrying out an act of violence when he opened fire at the busy Fort Lauderdale airport.

Santiago, who had earlier shown signs of "erratic behavior", arrived on Friday on a flight from Alaska.

At baggage claim he retrieved a 9mm semi-automatic handgun and ammunition that he had declared and stowed inside his checked luggage, then allegedly loaded the weapon in a bathroom and opened fire in the crowded baggage claim area of Terminal 2.

Once his ammunition was exhausted Santiago lay on the floor with his arms and legs spread out and peacefully surrendered when a sheriff deputy approached him, witnesses quoted in US media said.

The hail of bullets sent thousands scrambling for safety and shut down the airport, a major gateway to the Caribbean and Latin America, for about 16 hours.

If convicted of the charges Santiago could face the death penalty or life in prison, US Attorney Wifredo Ferrer said in a statement.

"Santiago started shooting, aiming at his victims' heads until he was out of ammunition," Ferrer said.

FBI special agent George Piro said agents were looking into the motives for the attack, including "continuing to look at the terrorism angle".

Piro said Santiago appeared to be acting alone and that "every indication" is that he followed rules in flying with the weapon.

Santiago is scheduled to make an initial court appearance on Monday.

'Erratic'

A former member of the Puerto Rico and Alaska National Guard, Santiago served in Iraq from April 2010 to February 2011. He ended his service in August.

On Nov 7, Santiago walked into the FBI's office in Anchorage, Alaska and complained that his mind was being controlled by national intelligence agencies, which were forcing him to watch Islamic State jihadist videos, authorities said.

This "erratic behavior" led agents to contact local police, who took him for a mental health evaluation, Piro said.