Two Second World War aircraft, as well as other metal objects have been discovered during studies of the seabed conducted with the assistance of the Italian Navy minesweeper Sapri.

The joint project between the Italian Navy, represented by the Italian Military Mission in Malta, and the Museums Department aims to identify archaeological features and create a marine heritage map, which would improve the policing of the threatened sites.

Reuben Grima, a curator at the National Museum of Archaeology, said the results of the project were "brilliant, considering the fact that the Sapri was at Malta's disposal for one week".

The research was carried out off the southeast coast of Malta and the aircraft, which are in a relatively integral state, were found off Hal Far.

According to the Aviation Museum Foundation's preliminary identification, one of the aircraft discovered is an American single seater fighter from the 1950s. Its cockpit was open, meaning that the pilot may have survived.

Other sonar readings are likely to indicate objects dating back to the 19th and 20th century, as they are of a ferrous nature, Mr Grima said.

He stressed the importance of underwater cultural resources, which have not yet been explored, or have been plundered by divers.

"By understanding them, we can protect them," he said, adding that the first step was to recognise and quantify the resources.

With the assistance of the Italian Navy and its high-tech equipment, data and unconfirmed reports were verified. In the case of vague indications of sites, they had now been precisely located, although further investigations would be required to complete the picture, as in the case of HMS Russell.

During the inspection and monitoring of recorded sites, the team came across a wreck, which has been plundered over the years. It once carried an extensive cargo of ceramics, dating back to the last century.

Mr Grima said that last year, persons had been apprehended at Customs with ceramics from the wreck, following reports that divers had been secretly stealing the cargo. Although it was not ancient, the ceramics were still valuable, he said.

The project also included the exploration of areas that had never been explored before, particularly in deep waters, which Malta did not have the resources to investigate.

Over the past week, the Sapri's divers and sophisticated equipment for underwater surveys and search operations, used normally to locate mines, was put to a more cultural use.

Its commanding officer, Lt Vitaliano Carboni, said the system used on minesweepers was compatible with marine archaeological research. Both the Italian Navy and the Museums Department were learning how to share resources, equipment and expertise.

The Sapri, which left Malta yesterday, is also equipped with a remote-operated vehicle, Pluto, manufactured in Italy and used to survey the seabed. The ROV can descend to depths of 300 metres and can record images and take photographs. It also easily manoeuvres through the wrecks.

The commander of the Italian Navy branch of the Italian Military Mission in Malta, Claudio Morgese, said the pilot project was the result of the Italian Navy's will to promote cooperation between Mediterranean countries.

The idea was to put its marine resources at the disposal of "more civilian purposes".

Speaking about the problems surrounding marine archaeological sites and how to treat them, Mr Grima mentioned that divers did not always communicate their finds to the Museums Department.

People have even tried trawling up finds and there was frequent souvenir hunting. Ropes have been discovered tied to wrecks, meant to make them easier to locate and guarantee a quick dive.

Although finds have been lifted out of the sea and exhibited in museums, there were several principles and bureaucratic measures to be followed before marine sites could be disturbed. The flag state of warships retained many important rights over them, meaning that intervention was impossible without consultation.

The issue of war graves also had to be considered, and vessels aboard which people had died were regulated by a War Graves Commission. Moreover, some wrecks could still have an owner.

Unfortunately, these points were often ignored by divers.

"Every time they lift objects off wrecks, they could be violating war graves," Mr Grima said, insisting on the need for education on the plundering of warships and the infringement of the rights of flag states.

Mr Grima expressed his concern at the fact that cultural objects were frequently being moved and trafficked without necessary authorisation.

Regulating illegal activity on the seabed and protecting underwater sites and relics was a headache throughout the Mediterranean. But Mr Grima believed in the effectiveness of collaboration and networking between the Malta Maritime Authority and the Armed Forces of Malta, the police and the Museums Department.

For example, collaboration between the MMA and the AFM had revealed a bell, stolen from a Second World War destroyer, on board a Belgian yacht. The bell is now on display at the Maritime Museum.

The global effort to regulate and control the protection of underwater resources has translated into an extension of the area even beyond territorial waters from 12 miles to 24 miles in the Culture Heritage Act.

"Now the area has to be policed and this is where the role of partnerships and supporting interventions becomes vital.

"It is essential that the exercise is continued."