Fort Hood gunman Ivan Lopez 'may have snapped after argument'
3 April 2014 Last updated at 22:34 BST
The US Army says there is a "strong possibility" a gunman who killed three people at a base in Texas was involved in an argument before the shooting.
Lt Gen Mark Milley formally identified the attacker as Specialist Ivan Lopez, 34, who later shot himself.
He told reporters there was "very strong evidence" that Lopez, who is originally from Puerto Rico, had an unstable psychological condition.
Sixteen others were wounded in the attack.