Championship leaders McLaren have been told they are under investigation by Italian prosecutors as the Formula One spying row shows no sign of abating.
McLaren face another World Motor Sport Council hearing on Thursday
Team officials were visited by court officers in the paddock at Monza on the eve of Sunday's Italian Grand Prix.
A McLaren statement described the visit as "wholly unnecessary", adding they "strongly suspected the nature and timing" was aimed at disrupting them.
The incident happened shortly before Saturday's qualifying session.
The team said they were "completely confident that were any proceedings of this type ever to be brought we would be completely exonerated".
McLaren already face a second World Motor Sport Council hearing in Paris on Thursday after new evidence recently surfaced in the "spygate" scandal.
The team were found guilty of fraudulent conduct at the first hearing after being caught in possession of technical information belonging to Ferrari, although no penalty was imposed due to insufficient evidence.
The latest allegation reportedly centres around an e-mail exchange between Alonso and test driver Pedro de la Rosa.
In a worst-case scenario, McLaren could be kicked out of the competition both this year and next.
They are currently 11 points ahead of Ferrari in the constructors' standings while British rookie Hamilton leads double world champion Alonso by five points in the drivers' title battle.
The spying row blew up when McLaren chief designer Mike Coughlan, who has since been suspended by the team, was found to have nearly 800 pages of Ferrari documents in his house.
Ferrari believe Coughlan received the documents from their former performance director Nigel Stepney.
Criminal proceedings are active against Stepney, who was sacked by Ferrari from his role as head of performance development in July.
Stepney is also being investigated for allegedly sabotaging the team's cars ahead of the Monaco Grand Prix in May.
A mysterious white powder was apparently discovered around the petrol caps of the cars driven by Felipe Massa and Kimi Raikkonen days before the race in Monte Carlo.
Stepney has strongly protested his innocence in both cases.