Spanish police said Sunday that they seized 6.5 tons of cocaine and arrested nine people after a U.S. tip-off led them to raid a ship off the Canary Islands a few days ago.

In a statement , police said the narcotics were hidden in the hold of the boat, which was flying a Tanzanian flag and had departed from Panama en route to Vigo, in north-west Spain. The cargo ship, which was approximately 177 feet long, had unusual structures on board which concealed the narcotics, officials said.

The Drug Enforcement Administration, the U.S. federal agency responsible for combating drug trafficking, provided key "information" that enabled the operation to succeed, the press release stated.

Police release video on social media showing officers on a speed boat intercepting the alleged drug-traffic

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