Andreas Lubitz, Germanwings Co-Pilot, Received Training in Arizona

— -- The co-pilot who was at the controls when the Germanwings flight crashed this week received some of his training in America, the airline's CEO revealed today.

Andreas Lubitz, 27, was a German citizen and started working for Germanwings' parent company Lufthansa at a flight training center outside of Phoenix in 2008, company officials said.

The facility, called Airline Training Center Arizona, was owned by Lufthansa and is used by its pilots in addition to other training locations in Germany, Switzerland and Austria, officials said.

A spokeswoman for Germanwings told ABC News that he also received some of his training in Bremen, Germany.

In spite of undergoing some of his training in 2008, he reportedly took breaks during the process and only became an official Germanwings pilot in 2013.

"Six years ago there had been an interruption to his training," Lufthansa CEO Carsten Spohr said at a news conference today. "We checked his skills and his competence and then he went back to training school. After that he was successful."

He went on to explain that the interruption lasted for a few months but he did not elaborate on the reason and said it was something that could happen regularly in their program.

Spohr said Lubitz passed training school "with flying colors."

"He was fit in all areas, 100 percent," Spohr said.

Lubitz belonged to a flying club in his hometown, and fellow member Peter Ruecker told the Associated Press that Lubitz had spoken about his time in Arizona.

"He seemed very happy that he got the job, beforehand he had training in the United States for three years, and we met him here again when he returned to renew his license and we talked for some time," Ruecker told the Associated Press. "He told us about how it was in America, how he did his training there, and he seemed to be very open and happy that he made it that far."

He had 630 hours of flying experience by the time he was at the controls during Tuesday's fatal crash into the French Alps, only 100 hours of which were on the same model plane, the Airbus A320, officials said.

U.S. law enforcement officials have offered cooperation on the investigation.

"The FBI has offered assistance to our French partners, who are leading the investigation into the crash of Germanwings Flight 9525," the agency said in a statement today. "We stand ready to fulfill any requests for information or assistance by crash investigators, as we work with partner nations whose citizens were impacted by this tragedy."

Editor’s note: A French prosecutor initially said Lubitz was 28 years old but a law enforcement official later determined that he was 27.

ABC News' Troy McMullen and Matthew Foster contributed to this report.