VIDEO: Couple who killed 14 at US centre for disabled 'looked as if they were on a mission'

At least two heavily-armed attackers who opened fire on a banquet at a California social services centre for the disabled, killing 14 people and seriously wounding more than a dozen others, looked "as if they were on a mission" authorities have said.

About four hours later, police hunting for the killers riddled a black SUV with gunfire in a shoot-out two miles from the late-morning carnage and a man and woman with assault rifles, handguns and "assault-style clothing" were killed.