Red Bull driver Sebastian Vettel, of Germany, drives in the rain followed by BMW Sauber driver Kamui Kobayashi, of Japan, during the Canadian Grand Prix, Sunday, June 12, 2011 in Montreal.Jacques Boissinot/The Canadian Press
"Undriveable," one driver told his team over the radio.
"You can't see anything at all," said another.
And so Formula One race officials decided to show the red flag with barely 25 laps in the books at the rain-soaked Canadian Grand Prix.
When the race was stopped at about 1:45 p.m., Red Bull's Sebastian Vettel was leading comfortably over Kemui Kobayashi, running an unexpected second in his Sauber, and Ferrari's Felipe Massa.
Pole-sitter Vettel's Red Bull, which has dominated F1 this season, was comfortably the fastest car in the race's early going, the two Lotus Renaults and the Ferraris battling with Kobayashi for podium spots.
Ferrari's Fernando Alonso, who started in the first row alongside Vettel, had slipped to eighth after pitting twice to change his rain tires.
Lotus' Nick Heidfeld and Vitaly Petrov were sitting fourth and fifth respectively after starting the race in the middle of the pack.
Formula One rookie Paul DiResta of Force India sat sixth.
It's expected the race will resume Sunday afternoon.
Two-time Canadian Grand Prix champion Lewis Hamilton, who won the race last year, managed only seven laps in the 2011 edition, which began under caution, his day ended when he tried to overtake teammate Jenson Button and the latter nudged him into the wall.
It was Hamilton's second collision of the day - on the first lap after the safety car pulled off Circuit Gilles Villeneuve he had a minor contretemps with Red Bull's Mark Webber in the first corner.
Webber briefly spun out but was quickly back on the track, having lost only one place.