The accident occurred when Raikkonen lost the rear end of his car exiting Turn 2 and collected Alonso, who was running to his left-hand side.
Both cars speared as one into the barriers, with the McLaren coming to a halt straddling the nose of the Ferrari and the top of the barrier.
Fortunately neither driver was hurt, and with the safety car deployed, they climbed unharmed from their wrecked cars.
The stewards announced that they would investigate the collision after the race, but after hearing from both drivers and examining video evidence they decided neither driver was at fault.
“I got a good start, and made up a lot of places into Turn One and Turn Two,” explained Alonso. “Kimi ahead of me had started on the Prime tyre, and he exited Turn Two with a lot of wheelspin - I went to overtake him and he lost the car to the left, and that’s exactly where I was - so we both went into the wall.
“Luckily, we’re both fine. It was a strange incident, because he lost the car in fifth gear, so it must have been very low grip.”
The crash means Alonso has now retired from four successive races for the first time in his career. It was Raikkonen’s first DNF since the season opener in Australia.