OAKLAND (CBS/AP) – A group of unusually determined thieves has stolen from an Oakland park a five-foot-tall brass port hole that once graced a 19th Century battleship.

City naturalist Stephanie Benavidez said that the colossal ring from the USS Maine probably was taken to be sold as scrap metal.

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Park officials noticed that the port hole had been knocked from its concrete foundation last week, but did not take immediate steps to secure it.

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It was discovered missing from Lakeside Park on Saturday, along with tire tracks and boards apparently used to roll it onto a truck. The ring weighed more than a ton.

The 1898 sinking of the USS Maine in a Havana accelerated tensions that eventually led to the Spanish-American war.

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