Stoofel Vandoorne and Lando Norris were due to stay on after yesterday's Brazilian GP to test Pirelli's 2018 compounds.
The McLaren-Honda team that was supposed to do a tire test this week in Brazil.
Members of staff from the Sauber F1 Team, Williams Martini Racing, the FIA and Pirelli all experienced frightening attacks on vehicles they were travelling in on Friday night, whilst a Pirelli auto is also believed to have been targeted on Sunday night, following the race.
On Sunday after the race, Pirelli was involved in an incident when team members leaving the track were also targeted, and the tire manufacturer has chose to cancel its testing with McLaren on security grounds.
But the two-day test, scheduled to take place on Tuesday and Wednesday, has now been scrapped after staff from McLaren and Pirelli understandably expressed their frustrations and unease over the apparent lack of security.
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"Following a robbery attempt, neutralised by Pirelli security, on a Pirelli van at the Interlagos circuit last Sunday...it has been made a decision to cancel the tyre test", Pirelli said in a statement. Pirelli is yet to confirm whether the Brazil test will be rearranged or whether the cancellation will hamper its preparations for next year's campaign.
Teams made changes to security plans while the police vowed to add an increased presence after dark near the circuit on Saturday, but Sauber was still the subject of another attempted attack the following night when its bus was rammed by a auto. Staff from Sauber were also held up as they left the circuit on Saturday. In both cases, the staff in question were unharmed.
A spokesman for Liberty Media, the sport's owners, said it was up to the circuit and local authorities to ensure safety this week.
"We are extremely disappointed with the events of the last week", an F1 spokesperson told Sky Sports News.
"But is not our call, and it is not our responsibility. People leaving the circuit are exposed and it is obvious that they are at a disadvantage and that is something that needs to be addressed".