The 24-year-old world champion claimed his second victory of the season when he established an early lead then held off McLaren's Kimi Raikkonen to win by less than two seconds on a dramatic afternoon at Albert Park.

Germany's seven-times world champion Michael Schumacher was among a handful of drivers involved in high-speed crashes that interrupted the race.

Schumacher's teammate Felipe Massa also wrecked his Ferrari when he slammed into a wall while Juan Pablo Montoya, Christian Klien, Jarno Trulli, Nico Rosberg and Vitantonio Liuzzi were also involved in accidents.

Ralf Schumacher steered his Toyota to third place ahead of fellow German Nick Heidfeld's BMW Sauber and Alonso's Italian teammate Giancarlo Fisichella.

Alonso has 28 points to 14 for Fisichella and Raikkonen. Schumacher and Button are level on 11. Renault lead the constructors' standings with 42 to McLaren's 23.