Race abuse of F1 star Hamilton
Hamilton, 23, was jeered and insulted when he moved between the McLaren motor home and the team's garage at the Circuit de Catalunya, in Montmelo, near Barcelona.
Formula One's governing body, the FIA, has now warned that any repeat of the abuse will result in action.
Reports suggest the FIA may even consider stripping the Circuit de Catalunya of its Grand Prix.
According to reports in the Spanish press, circuit director Ramon Pradera instructed staff to erect barriers around the team's paddock because of fears for Hamilton's safety.
Banners were removed and the stands directly above McLaren's garage were cleared of spectators to ensure that no debris could be thrown down when the car returned to the pit lane.
"We would like to make a plea to the fans to behave correctly," Mr. Pradera said. "No type of offensive behavior can be tolerated."
A spokesman for the FIA said: "The FIA is surprised and disappointed at the abuse directed at Lewis Hamilton.
"An act of this kind is a clear breach of the principles enshrined in the FIA statutes and any repetition will result in sanctions." Metro.co.uk