Image caption Panamanian officials said two jet fuselages were found in containers on the Chong Chon Gang

Panamanian security forces searching a North Korean ship detained for illegally carrying weapons have found two military jet fuselages.

The ship was seized last week after police found undeclared military cargo hidden under bags of sugar in its hold.

Cuba said it had sent the weapons to North Korea for repairs.

Panama has asked the UN to investigate whether there has been a breach of the sanctions against North Korea, which ban the supply of arms to Pyongyang.

'Obsolete weapons'

Prosecutor Javier Caraballo said that "in the containers that we've opened up to now, we have found two fuselages of MiG-21 jets. We've also found some anti-aircraft radars, of the type to launch anti-aircraft weapons".

Chong Chon Gang's route Departs from Nakhodka in Russian far east (200km east of North Korean border) Arrives at Pacific side of Panama Canal Leaves the Panama Canal on the Caribbean side heading for Havana, but disappears from satellite tracking Arrives back at Panamanian port of Manzanillo; later searched for contraband. Weapons uncovered

The Chong Chon Gang was stopped on 15 July on suspicion of carrying drugs, but instead police found military material on board.

The authorities in Havana admitted being behind the stash, saying they were Soviet-era arms from Cuba headed for repair in North Korea.

They said that the ship was carrying 240 tonnes of "obsolete" defensive weapons, including two anti-aircraft missile complexes, nine missiles in parts and spares, two MiG-21bis fighter planes and 15 MiG engines.

Panama's Attorney General Ana Belfon said the jet fuselages still smelled of fuel.

"You are all here and are sensing the strong odour of fuel, to such a degree that no-one can know what danger Panama was put in," she told reporters at the port of Manzanillo, where the search is being carried out.

Officials said seven containers had been unloaded and opened so far, but they suspected more were still hidden underneath the ship's official cargo of 10,000 tonnes of sugar.

Panamanian President Ricardo Martinelli said that there appeared to be 27 containers on board.

"As you can see we're doing the work and opening them one by one to make an inventory of everything," he said while visiting the team inspecting the containers.

Security Minister Javier Mulino said a team of more than 300 people had been working around the clock to remove the bags of sugar under which the containers were concealed.

The 35-strong North Korean crew have been charged with endangering Panama's internal security.

Suspicious journey

The Chong Chon Gang left Russia's far east on 12 April and travelled across the Pacific Ocean before entering the canal at the start of June, with Cuba as its stated destination.

The ship disappeared from satellite tracking systems after it left the Caribbean side of the canal, resurfacing on 11 July.

Experts say this may indicate that the crew switched off the system that automatically communicates details of their location.

It was stopped near Manzanillo on the Atlantic side of the canal on 15 July.

Panama says experts from the United Nations Security Council will arrive on 5 August to inspect the weapons.

Under UN sanctions, the supply of arms to North Korea is prohibited in the dispute over its controversial nuclear programme.