Brazilian Vice President Jose Alenca has declared three days of mourning for 228 passengers and crew missing and presumed dead after an Air France plane crashed into the Atlantic on Monday.

Earlier Brazilian Defence Minister Nelson Jobim confirmed that debris found 1,000 kilometers (650 miles) off Brazil''s northeast coast in the Atlantic belonged to Air France Flight 447.

The plane sent an automatic signal to airline maintenance computers from the area on Monday indicating several technical failures. No further contact was made with the aircraft.

Brazil''s Air Force found airplane seats, white plane parts, and an orange buoy and traces of oil and kerosene on Tuesday floating over a 5-kilometer-stretch of the Atlantic''s deepest waters.

No human remains have so far been discovered in the area and no parts of the plane have been pulled to the surface. The first search vessel is to arrive at the scene where the wreckage was found later on Wednesday.

The missing passengers include 61 French nationals, 58 Brazilians, 26 Germans, and citizens from 33 other countries. Eight children were on the plane. One Russian, Andrei Kiselyov, is believed to have been on board, but the Russian Embassy in Paris has yet to confirm the information.

Lightning has been suggested as a possible cause of what appears to be the worst plane crash since 2001. However, French authorities are refusing to rule out terrorism.

Russian President Dmitry Medvedev has sent condolences to the French and Brazilian leaders over the tragedy.