Reports began to surface earlier in the morning that some Mercedes personnel were robbed as they left the Interlagos track last night.
Members of the FIA and Williams were also caught up but it was claimed nobody was hurt.
However, ahead of third practice, Hamilton revealed his team had been caught up in an armed robbery.
Hamilton tweeted: “Some of my team were held up at gun point last night leaving the circuit here in Brazil.
“Gun shots fired, gun held at ones head.
“This is so upsetting to hear.
“Please say a prayer for my guys who are here as professionals today even if shaken.”
Hamilton then called on F1 chiefs to provide greater protection for staff.
He added: “This happens every single year here. F1 and the teams need to do more, there’s no excuse!”
It is the second year in a row that a member of Hamilton’s team had been robbed on Grand Prix weekend.
In 2016 ahead of the Mexican Grand Prix, a gunman held up a chauffeur-driven car and took wallets and watches as a team member was being taken from Mexico City’s airport to the team’s hotel in the capital.
