German police have searched the home of co-pilot Andreas Lubitz in Duesseldorf and seized material that will now be examined as part of the investigation into the crash that killed 150 people in the French Alps.
French investigators believe Lubitz locked himself inside the cockpit and then intentionally smashed the Germanwings plane into a mountainside.
A spokeswoman for Duesseldorf police denied reports Friday that the officers had made any significant discovery yet.
"No crucial piece of evidence has been found yet," Susanna Heusgen told The Associated Press.
Duesseldorf prosecutors say they plan to release an update on their investigation around noon (1100 GMT, 7 a.m. EDT).
7 a.m. (0600 GMT, 2 a.m. EDT)
The co-pilot who authorities believe intentionally crashed an airplane into the French Alps, killing all 150 people on board, likely first honed his flying skills for months in Arizona.
Lufthansa Group, which owns Germanwings airline, said Thursday that 27-year-old Andreas Lubitz trained in Bremen, Germany, and Phoenix starting in 2008.
A Facebook page bearing his name lists Phoenix Goodyear Airport among his interests. The airport houses Airline Training Center Arizona, a Lufthansa-owned training facility.
Aviation experts say students there log flight hours and attend classes on navigation in an 18-month period. On Thursday, German and Lufthansa flags outside the facility were flying at half-staff.
Sunshine and vast air space have historically made Arizona a popular location for pilot training.
French prosecutors say Lubitz locked his co-pilot out of the cockpit of Germanwings Flight 9525 on Tuesday before the jet slammed into the mountainside.