The FIA is to launch an investigation after spectators managed to get onto the track in Melbourne immediately after the Australian Grand Prix.
Cars were still on their cool-down laps after the chequered flag at the time. Fans managed to get through security fences and onto the track.
Television pictures showed cars streaming past the fans spilling onto the circuit. Although not at race speed, the cars were still moving at up to motorway levels.
"It was mad - in a positive way - when there were people running on track going wild with Ferrari flags," said race winner Sebastian Vettel. "It was unbelievable."
The race organisers and the sport's governing body were distinctly less impressed.
Spectators are often allowed to come onto the circuit to take part of the podium celebrations. However, that is part of a controlled process once all cars are safely back in pit lane
"Normally, spectators are only allowed on the track once the course car completes the lap behind the last driver in the field," Formula 1 race director Charlie Whiting said.
"This time, for some reason the gates were opened in turn 15 before this happened. There were probably some overly euphoric Ferrari fans," he told Auto Motor und Sport.
"Fortunately, no dangerous situation arose but we will investigate what happened," said Whiting.
The boss of race promoter Australian Grand Prix Corporation agreed that what had happened was "a mistake in the signals".
"I am concerned because we have very, very strict processes that for 21 races have worked beautifully so something went amiss," Andrew Westacott told Speedcafe.
An initial investigation conducted by circuit operator CAMS found that spectator gates had been opened "without clearance from race control".
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