German airline Lufthansa said Tuesday that it has no information yet about the crash of a jet belonging to its Germanwings subsidiary, describing it as a "dark day."
"We do not yet know what has happened to flight 4U 9525," Lufthansa chief executive Carsten Spohr said via Twitter.
"My deepest sympathy goes to the families and friends of our passengers and crew on 4U 9525. If our fears are confirmed, this is a dark day for Lufthansa. We hope to find survivors."