A memorial service was held for Clifton College Preparatory School pupil Alexander Bjoroy who died with nearly 230 others in the Air France tragedy.

Alexander, 11, had spent half term with family in Rio de Janeiro, Brazil, and was on board the Airbus A330 aircraft which crashed mysteriously into the Atlantic.

The service included a tribute from his family, which was read by headteacher John Milne.

It said: "The world was his home, Alexander embraced other cultures and respected them greatly.

"He loved to travel and see and experience new places and people.

"We were very fortunate to share so many marvellous experiences together in his short life.

"Alexander loved many things, his sister, his mum and dad and also his extended family. He loved his friends, sport – especially rugby – but was also learning to surf in Brazil."

The Air France flight 447 took off last Sunday and was flying to Paris with 228 passengers and crew on board when it disappeared.

It is believed the aircraft ran into storms approximately 350 miles off the coast of Brazil.

Alexander, who was one of five Britons on board, was being chaperoned on the flight and was to be met by relatives in Paris.

Search teams were today concentrating their efforts in a part of the Atlantic where two bodies believed to be from the missing flight were found.

Yesterday's discovery came on the day French investigators said the communications system on flight AF 447 transmitted 24 error messages ahead of the flight's disappearance and its autopilot was not working.

Colonel Jorge Amaral, a spokesman for the Brazilian air force, said two male bodies were recovered from an area where the jet is believed to have crashed.

They were picked up roughly 400 miles (640km) northeast of the Fernando de Noronha islands off Brazil's northern coast, he added.

A leather suitcase containing a plane ticket for the flight and a backpack with a laptop and a vaccination card were also found.

The bodies were being transported to the islands for identification as investigators continued to search an area of the ocean stretching several hundred square miles.

At a briefing in Paris on Saturday, the investigators said the Airbus A330's communication system transmitted 24 error messages ahead of the flight's disappearance.

Paul-Louis Arslanian, the head of the French agency leading the crash investigation, said it was not clear if the autopilot had been switched off by the pilots or had stopped working because it received conflicting airspeed readings.

More than half of the 24 error messages – 14 – were sent within the space of one minute, from 3.10am BST to 3.11am BST.

The messages showed "inconsistencies" between measured velocities and indications of systems failures including the autothrust and autopilot, the investigators said.

But Mr Arslanian warned the error signals were "not designed for investigations" and only gave an indication as to the status of particular systems.

Investigators also said Air France had not acted on a recommendation to change airspeed-detecting instruments on the aircraft before the plane disappeared.

Alain Bouillard, leading the investigation, said Airbus had recommended to all its airline customers that they replace speed-measuring instruments known as Pitot tubes on the A330, the model that crashed, but "they hadn't yet been replaced" on that aircraft.

But investigators warned that it was too early to draw conclusions about the role of Pitot tubes in the crash, saying Airbus had made the recommendation for "a number of reasons".

Meteorologists said the Air France jet entered an unusual storm with 100mph updrafts that acted as a vacuum, sucking water up from the ocean.

The moist air rushed up to the plane's high altitude, where it quickly froze in minus-40 degree temperatures. The updrafts also would have created dangerous turbulence.

David Learmount, operations and safety editor of Flight International magazine, said: "The fact that the autopilot was not working is not the cause of this accident."

He said it was "not at all unusual" for the autopilot to cut out and added "it's not the cause, it's the symptom" of this accident.

"It's designed to cut out at any time that it receives conflicting messages, which we know it was," he said.

"It's designed to cut out rather than control the airplane in an unsafe way - it's not an intelligent system, it doesn't know which of the data are correct."

He said the pilots would have been alerted with a loud warning system when the autopilot disengaged.

US President Barack Obama said the United States had authorised all of the US government's resources to help investigate the crash.

France is sending a submarine, the Emeraude, to try to detect signals from the aircraft's black box recorders, said military spokesman Christophe Prazuck. The submarine is expected to arrive in the area next week.