Two years into construction of the bridge, at 11:50 am on 15 October 1970, the 112-metre (367-foot) span between piers 10 and 11 collapsed and fell 50 metres (164 feet) to the ground and water below. Thirty-five construction workers were killed and 18 injured, and it remains Australia's worst industrial accident. Many of those who died were on lunch break beneath the structure in workers' huts, which were crushed by the falling span. Others were working on and inside the span when it fell. The whole mass plummeted into the Yarra River mud with an explosion of gas, dust and mangled metal that shook buildings hundreds of metres away. Nearby houses were spattered with flying mud. The roar of the impact, the explosion, and the fire that followed, could be clearly heard over away. On the following morning, 16 October, Sir Henry Bolte (Premier of Victoria) announced that a Royal Commission would be set up immediately to look into the cause of the disaster. The Prime Minister, John Gorton, said: "I am sure the whole of Australia is shocked and saddened by the serious accident at West Gate Bridge. Please extend my deepest sympathy to all those families to whom this tragic event has brought such grief."