investigators, of course, are trying to get a clearer picture of who co-pilot andreas lubitz was. they searched his apartment in dusseldorf thursday. we learn more from our correspondent in germany. >> reporter: the house where andreas lubitz's parents live, shuttered and guarded by police. investigators, the only ones granted access. we were hold the grandparents lived in this nearby house, but they're unwilling to speak about the man french prosecutors say may have deliberately crashed flight 9525. i ask if they're relatives? no, thank god we're not, getting into a police car. we're just trying to get away. but guiding was clearly a young passion for the young lubitz. at the ages of 12 and 14, lubitz was a regular fixture here,