magistral

All flight and train reservations are recorded in an FSB database called Magistral.

An FSB agent could use Magistral to track a target with this degree of precision, according to Mr Grozev.

Those brokers acquired the data from corrupt officials who have access to Magistral.

The BBC also used data that was given to us, without payment, from sources who have access to copies of Magistral.

Bellingcat has previously used data from Magistral to investigate assassination attempts in Russia.