Another officer in Tennessee was badly wounded hours later after being shot searching for suspect.
While the child's name, age, gender or location wasn't released, the Florida Department of Health said the child hadn't received a flu shot.
The UK's National Cyber Security Centre is a relatively new agency responsible for protecting Britain from cyber threats. The U.S. has nothing like it.
The Saudis are "determined to get to the bottom" of what happened, said the secretary of state.
The student, a local man acting alone, killed himself after the attack that killed 17 and injured 40, said an official.