A Lockheed Martin-manufactured Hellfire missile meant for a training exercise in Europe found its way to Cuba while on its return journey to the US in 2014, and has not been returned by Havana yet, reported The Wall Street Journal.

Even though the missile is a dummy, there are concerns over Cuba sharing the technology with countries adverse to the US, like Russia, China or North Korea, reported WSJ.

The US, which restored diplomatic ties with Cuba after more than 50 years, has been spurring Cuba to return the missile, reported WSJ.

The missile was a dummy meant for a NATO exercise in Spain, where it was shipped properly. However, on the circuitous way back — through Spain, Germany and France — to US, the Hellfire was shipped to Havana instead of Florida.

A US official familiar with the matter confirmed the incident to Associated Press, on condition of anonymity.

The air-to-surface missile can be launched from a combat helicopter like the Apache or a drone like the Predator. It weighs 45 kg and is laser-guided. It is meant for attacking ground targets like tanks and bunkers.

Investigations are being carried out about whether the missile was diverted to Cuba due to gross error or espionage. The US Defence department is working with Martin Lockheed, which was authorised to ship the missile for the NATO exercise, to get the weaponry back from Havana.

The US official blamed the misplacement of the missile on Lockheed's freight carriers.