Citroen's Ma Qing Hua took his first win of the 2015 World Touring Car Championship in Vila Real in dramatic circumstances as red flags ended the race early
Ma led from the reverse-grid pole, staving off a challenge from team-mate Yvan Muller, who started second.
Chaos ensued behind as Lada's Jaap van Lagen got away slowly from third place alongside team-mate Nicky Catsburg, and Honda's Tiago Monteiro tried to dive between the two Vestas.
The gap began to close as Monteiro was already well committed and the Civic bounced off both before its trajectory took it into a heavy impact with the Armco, followed by Van Lagen's car, which also lost a rear wheel and part of its suspension in the impact.
Momentum sent the wheel bouncing back down the track, collecting the Chevrolet of 14th-place starter Stefano D'Aste and breaking his right-rear suspension upright.
All the other cars made it through, although Sebastien Loeb nearly collected team-mate Jose Maria Lopez as he swerved left to miss the accident.
The second group of Citroens made their usual fast start but could only pass Hugo Valente's Chevrolet, tucking in behind the privateer Honda of Norbert Michelisz.
Following a five-lap safety car deployment Ma led the restart and consistently pulled away from Muller, who in turn built a gap to Catsburg, who was being harried by a train led by the second factory Honda of Gabriele Tarquini.
The Tarquini-Michelisz-Loeb-Lopez train followed in close attendance until Catsburg ran wide at the Turn 21 right-hander on lap 10.
Tarquini breezed straight past, while Michelisz and Loeb went either side as Catsburg recovered.
Loeb found himself trying to go around the outside of both of them as the next right-hander loomed, the three cars came together, and Loeb went sideways into the barrier.
By then Ma had a four-second lead over Muller, and although Tarquini began to reel in the second Citroen, the race was then stopped when Catsburg slewed wide in a high-speed section on lap 13 and made a hard impact with the barrier, leaving debris across the track.
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