Updated

Mexico's navy Tuesday seized more than a ton of cocaine stuffed inside frozen sharks by smugglers.

Military pressure is forcing drug gangs to go to greater lengths to conceal narcotics bound for the United States.

Navy officers cut open more than 20 shark carcassesfilled with slabs of cocaine after checking a container ship in a port in the southern Mexico state of Yucatan.

X-ray machines and sniffer dogs had helped uncover the drugs.

"We are talking about more than a ton of cocaine that was inside the ship," Navy Commander Eduardo Villa told reporters.

"Those in charge of the shipment said it was a conserving agent but, after checks, we confirmed it was cocaine."

Gangs have been hiding drugs in sealed beer cans, religious statues and furniture, as Mexico's military cracks down on the cartels moving South American narcotics north.

President Felipe Calderonhas sent 45,000 troops and federal police across Mexico to try to crush powerful smuggling organizations.

But traffickers armed with a huge arsenal of grenades and automatic weapons are far from defeated, worrying Washington as violence spills over into US states, such as Arizona.

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