When the Spanish high-speed rail train derailed in the country’s northwest last week killing 79 people, the driver of the train was on the phone with his employers.

Investigators say they opened the “black box” recorders to find out what caused the crash. 

Francisco Jose Garzon Amo had received a call from staff at Spain’s state-owned railway about the route he was driving, and was consulting maps or looking at papers, investigators say.  They also say the train’s brakes were activated shortly before the fatal bend at Santiago do Compostela.  The train was going 153 kilometers per hour at the time.

The chairman of the national railway company Renfe said drivers are required to disconnect their private phones while on the job.  Land lines are recommended for safe communications and corporate phones are allowed exclusively for instructions.