Authorities are investigating after someone broke into the Neil Armstrong Air and Space Museum in Ohio and stole a rare scaled-down replica of the 1969 Lunar Excursion Module that landed on the moon.

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An alarm at the museum alerted police of the break-in around midnight Friday, according to a release from Wapakoneta police.

Officers discovered someone broke into the museum and stole the sold gold replica of the lunar module, which stands 5 inches tall and about 4.5 inches wide.

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"This piece is very rare as it was presented to Neil Armstrong in Paris, France, shortly after the moon landing," police said.

The piece is one of only three that were made, one for each of the astronauts who completed the mission, police said.

The FBI and the Ohio Bureau of Criminal Investigation assisting Wapakoneta police in the investigation.