Lockheed Martin reports two new successful flight tests of its Trident II D5 fleet ballistic missile by the U.S. Navy.

The tests of the missile were conducted in the Pacific Ocean from a submerged Ohio-class submarine.

The unarmed missiles, manufactured by Lockheed Martin, were converted into test configurations using kits with range safety devices and flight telemetry instrumentation that were produced by the company.

"These latest test flights demonstrate the reliability of the D5 missile and the readiness of the entire Trident Strategic Weapon System every minute of every day," said Mat Joyce, vice president of Fleet Ballistic Missile programs and deputy for Strategic & Missile Defense Systems, Lockheed Martin Space Systems. "The Navy program office, the submarine crews and the industry team never rest to ensure the safety, security and performance of this crucial deterrence system."

The two firings bring the number of successful flight tests of the missile since 1989 to 155, Lockheed Martin said.

The Trident II D5 is a three-stage ballistic missile. It can travel more than 4,000 nautical miles and carries multiple, independently targeted re-entry bodies.