Germanwings Flight 4U 9525 experienced a steep and fast drop before it lost contact with air traffic control and crashed into the French Alps on Tuesday, the Lufthansa subsidiary’s CEO said at a press conference. Investigators are trying to determine what caused the loss of altitude, including whether it was intentional by the pilot, who had flown 10 years with the company and logged 6,000 flight miles with the type of plane involved in the crash.

“Right now the most important [thing], however, is our deep sorrow for our passengers, their relatives as well as relatives of our crew members since they have lost their dear loved ones,” said Germanwings CEO Thomas Winkelmann, according to a translation from France 24’s livestream coverage of the press conference. “Our thoughts and prayers are with the victims. At the same time, understand we will work with authorities to find out reasons why this plane crashed as quickly as possible.”

Two babies were among the 144 passengers aboard the Airbus A320, Winkelmann said. About 67 German nationals were believed to be on the Barcelona-to-Dusseldorf flight. The passengers and six crew are believed to have died in the crash in the south of France.

The Germanwings flight dropped to a very low 8,000 feet from its normal cruising altitude and further dropped in a descent that lasted eight minutes, Winkelmann said. Air traffic control lost contact with the plane when the aircraft was about 6,000 feet. The plane crashed shortly thereafter, he said.

The A320 was delivered to Lufthansa from Airbus in 1991 and was flown by the German airliner until 2010, when the plane was handed over to Germanwings, its low-cost subsidiary. A routine check on the aircraft was last performed Monday by Lufthansa’s technical department, which found “nothing remarkable” in the review, Winkelmann said. A more thorough review was undertaken in 2013.

The flight’s captain, whose name was not released, was a 10-year veteran of Lufthansa and Germanwings, Winkelmann said. He had flown some 6,000 hours on the Airbus A320.

Winkelmann said he didn’t believe the age of the aircraft was a factor in the crash. “The Airbus 320 has not recorded the slightest accident since it’s been used by Lufthansa group,” he said. “We use different models that are as old as this one.”

Germanwings Chief Pilot Kenan Scheib said he doubted the plane’s computer played a role in the accident since it was recently upgraded.  “Theres no reason why fault should have occurred with the computer,” Scheib said.

Germanwings said it will provide a list of names of people on the flight only after all the families are notified. A Lufthansa team was on its way to the crash site Tuesday to help investigate “why our plane suddenly crashed,” Winkelmann said.