Air force pilots saw metallic objects, plane seats, an orange buoy and jet fuel stains in the water about 650 km north of the archipelago of Fernando de Noronha off Brazil’s northeastern coast. Brazil’s navy said a Dutch commercial ship was nearby and would arrive in the area shortly.

The chances of finding survivors appeared close to nil.

“The plan now is to focus our efforts to collect the debris and try to identify if they belong or not to the Air France plane,” Brazilian Air Force Colonel Jorge Amaral told reporters in Brasilia. “We can’t really say this is part of the airplane. The command center needs to have at least one piece of the debris with a serial number to confirm that it belongs to the airplane.”

Three Brazilian air force Hercules planes took off from the islands of Fernando de Noronha, which sit about 370 km off the coast of South America, early on Tuesday to look for traces of the Airbus A330. The area is near where the last contact was made with the flight that took off for Paris from Rio de Janeiro on Sunday night and went missing in storms four hours later without sending any distress signal.

Air France flight 447 sent an automatic message reporting electrical faults before it went missing. But aviation experts said they did not have enough information to understand how a plane with an excellent safety record could have crashed.

“All scenarios have to be envisaged,” French Defence Minister Herve Morin said on Europe 1 radio. “We can’t rule out a terrorist act since terrorism is the main threat to Western democracies, but at this time we don’t have any element whatsoever indicating that such an act could have caused this accident,” Morin added.

The flight was carrying 216 passengers from 32 countries, including seven children and one baby. Sixty-one were French, 58 Brazilian and 26 German.

French minister Jean-Louis Borloo said it was crucial to locate the black boxes, or flight recorders, programmed to emit signals for up to 30 days. This is a race against the clock, Borloo told RTL radio.