Washington (AFP) - A dummy training version of a US Hellfire missile was shipped to Cuba after an apparent mix-up by commercial cargo handlers in Europe, a source said Friday, confirming media reports.

The source familiar with the issue, who spoke on condition of anonymity because of US laws protecting the confidentiality of commercial arms deals, said the shipment was made in 2014.

The Hellfire is produced by US defense giant Lockheed Martin along with an inert version known as a "Captive Air Training Missile" stripped of its warhead, fuse, gyroscope and motor.

In summer 2014, Lockheed received export approval from the US State Department to send a dummy missile to a NATO training exercise in Spain and flew one out of Orlando, Florida.

According to the Wall Street Journal, after the exercise the missile was crated up to be shipped back to Florida, again as commercial cargo air freight -- and went missing.

It is now believed that the crate was misdirected and loaded into the hold of a commercial cargo jet, then flown to Havana along with ordinary non-military air freight.

According to the report, confirmed to AFP by the anonymous source, the package arrived in communist Cuba and has been seized by the authorities there.

The Journal's report said the incident raised fears that Cuba -- despite the recent thaw in its relations with Washington -- might sell US missile secrets to rivals like Russia or China.

But the Hellfire missile, commonly fired at ground targets from a helicopter or a drone, has been in service since 1984, and has been delivered to more than two dozen countries.

On Thursday, for example, the US Defense Security Cooperation Agency approved delivery of 5,000 Hellfire and 10 Captive Air Training Missiles to Iraq, which has ties to Russia and Iran.

Lockheed Martin notified the State Department of the incident when it realized the missile was missing.

The US Justice Department is investigating the matter, according to the Wall Street Journal, and US diplomats have requested -- so far in vain -- that Cuba return the missile.