Investigators carried out searches Thursday at two homes of the German co-pilot who officials say appears to have deliberately crashed a plane into the French Alps, a German prosecutor said.

"Both the home of the co-pilot in Duesseldorf and the home in Montabaur have been searched," said chief public prosecutor Ralf Herrenbrueck in the western city of Duesseldorf.

Andreas Lubitz, the 28-year-old co-pilot who French authorities believe deliberately brought down a Germanwings jet Tuesday, lived with his parents in the western town of Montabaur, while also keeping a flat in Duesseldorf, Montabaur mayor Gabriele Wieland told DPA news agency.

Duesseldorf prosecutors have opened a parallel inquiry to the main investigation under way in France as many among the 150 crash victims were from the German region.

The city's public prosecutor said in a written statement that searches in Duesseldorf and other places were aimed at "in particular, the discovery and securing of personal documents" to help clarify the situation.

In Montabaur, a town of around 12,500 inhabitants, a police cordon had been set up around the Lubitz family home and men wearing gloves came out carrying briefcases, bags and boxes, an AFP journalist saw.

READ: No indication of co-pilot's motives: Lufthansa chief

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