German prosecutors say the co-pilot of Germanwings Flight 9525 appears to have researched suicide methods and cockpit door security in the days before the plane crashed last week.

Dusseldorf prosecutors said that investigators found a tablet computer at Andreas Lubitz's apartment. They said they were able to reconstruct searches from March 16 to March 23.

Investigators believe the 27-year-old Lubitz locked his captain out of the A320's cockpit on March 24 and deliberately crashed the plane. All 150 on board died.

Prosecutors' spokesman Ralf Herrenbrueck said that search terms included medical treatment and suicide methods.

On at least one day, the co-pilot looked at search terms involving cockpit doors and their security methods.

Meanwhile French prosecutors said the second black box recorder from the Germanwings jet has been found.

The second black box is the data recorder and contains readings for nearly every instrument.

An official in Marseille Prosecutor Brice Robin's office says he will give a news conference later today about the discovery.