SAN DIEGO (Reuters) - Sixty-four sailors will be discharged from the U.S. Navy after they were caught using or distributing drugs, in most cases the designer drug Spice, the Navy said on Thursday.

The sailors are assigned to the nuclear submarine USS San Francisco, the aircraft carrier USS Carl Vinson, and a floating dry dock, the Navy said.

Osama bin Laden was buried at sea from the Carl Vinson in May after he was killed in a raid by U.S. Navy Seals on his Pakistan hide-out. The ship normally has 5,000 sailors on board during deployment.

"The Navy's policy on drug abuse is simple and clear -- zero tolerance," Vice Admiral Gerald Beaman, commander of the Third Fleet, said in a written statement.

"Drug use puts lives and missions at risk and undercuts unit readiness and morale," Beaman said.

The sailors facing separation from the Navy include several who are being investigated for distributing the drugs and who could face additional legal action, the Navy said.

Spice is a synthetic drug that mimics the effects of marijuana.

Six sailors have also admitted to using cocaine and one was found to have used methamphetamines, the Navy said.

(Writing by Dan Whitcomb; Editing by David Bailey)