PANAMA CITY (AP) -- Panama has filed charges against the crew of a North Korean ship seized as it tried to pass through the Panama Canal while carrying obsolete weaponry from Cuba hidden under bags of sugar, possibly in violation of U.N. sanctions.
Ramon Lopez, operations director for Panama's National Aeronautics Service, said authorities decided to stop the ship after getting intelligence from the United States and other countries about a suspicious North Korean vessel.
"There was a lot of tension and strong resistance during the inspection," said Lopez, adding that the inspection lasted for three days.
Panama's top prosecutor, Javier Caraballo, said the captain and 35 crew members have been charged with "attempts against Panama's security" and "illegally transporting undeclared military equipment."
The North Korean Foreign Ministry had urged Panama to let the crew go, but Caraballo said late Wednesday that the charges will force the crew to remain while authorities search the ship further. Investigators were still unloading sacks of raw brown Cuban sugar Thursday.
Caraballo said the North Korean sailors could face four to six years in prison if convicted on the "attempts against Panama's security" charge alone.
"According to the ship's manifesto, this boat only had 220,000 quintals of sugar. It never declared the military weapons, and obviously this in itself is a violation of the rules and it puts in grave danger all who transit through the Panama Canal," he said.
The captain and crew members have refused to speak to authorities, Caraballo said.
Caraballo also said shipping the weapons through the canal likely violated U.N. resolutions that ban North Korea from buying and selling missiles and other heavy arms.
Cuba has said it was sending the weapons, including missiles, two jet fighters and radar equipment, for repair in North Korea.
Panama's government announced Wednesday night that visas issued by the Panamanian Embassy in Cuba's capital to two North Korean officials based there were not valid because they were not authorized by prosecutors.
The diplomats had arranged to travel to this Central American country to inspect the ship and give their country's version of events, but authorities said Panama would have to re-issue the visas.
"Only the attorney general may authorize citizens of the Republic of North Korea to conduct inspections of the ship because it's a seized ship," the presidency said in a statement. "The requested document in our embassy is not a valid one."
The discovery of the weapons aboard the freighter Chong Chon Gang on Monday is expected to trigger an investigation by the U.N. Security Council committee that monitors sanctions against North Korea. Panamanian officials said U.N. investigators were expected in Panama on Thursday.
Panamanian security officials described to The Associated Press some tense moments aboard the ship after they stopped and boarded it July 10 for an inspection on suspicion it was carrying drugs.
Officials inspected the freighter while anchored a few miles from the port city of Colon. Officers then ordered the ship moved to a pier at the international port of Manzanillo.
Upon arrival, the captain and 35 crew members started to act aggressively, said Lopez of the aeronautics service. He said the captain went into a bathroom and came out holding a knife against his neck, threatening to cut himself.
"He made a small wound on his neck," Lopez said.
A sailor was able to neutralize the captain and then the rest of the crew got restless and agents had to separate them, Lopez said.
"They started yelling and beating on a table, on the ship walls," Lopez said. "They were demanding we free them."
The captain was taken to a hospital in Colon, where he is in stable condition.
Panamanian President Ricardo Martinelli, who first announced the seizure of the ship Monday, said the captain had tried to commit suicide and had a heart attack.
Before the ship arrived in Manzanillo, the agents discovered that under sacks of sugar there was a metal container.
They opened the container and first found a radar control system for surface-to-air missiles, Panamanian authorities said.
Most of the crew was taken off the ship except for two sailors who remain to act as witnesses of the inspection by authorities, Caraballo said.
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