UPDATE, TUESDAY, DECEMBER 12: The Western Freeway between Ballan and Bacchus Marsh has reopened after six separate collisions, involving 30 vehicles in the Myrniong area on Monday, December 11. Emergency crews were first called just before 4pm. Police said one collision involved around 14 vehicles, but one one was seriously hurt. "Five other separate collisions took place in the surrounding area, also on the Western Freeway," a Victoria Police spokesperson said. "Two males were taken to hospital in a critical condition, each involved in separate collisions. "Twenty other people from various collisions were treated for non-life-threatening injuries. "The cause of the collisions appears to be due to heavy fog in the area and drivers not driving to the conditions." While the freeway has been reopened, speed has been reduced to 60kmh while repairs on the road can continue. "Motorists are asked to remain vigilant for fog along stretches of the Western Freeway between Melton and Ballarat," the Department of Transport said on Tuesday morning. The closure of both of the westbound and eastbound lanes caused chaos during the peak hour rush. MONDAY, DECEMBER 11, 2023: Twenty people have been treated by paramedics, including one who is in critical condition, after several multi-vehicle crashes in thick fog on the Western Freeway at Myrniong on Monday afternoon. Emergency services were called to the scene just before 4pm, with both of the westbound and eastbound lanes between Ballan and Bacchus Marsh closed for the afternoon and well into the evening. It is not known when the freeway will re-open. A Victoria Police spokesperson said multiple cars are involved in the incident. "It's believed more than 20 vehicles are involved due to heavy fog in the area," the spokesperson said. An Ambulance Victoria spokesperson said paramedics treated nearly two-dozen patients. "A total of 20 patients were transported to hospital," the spokesperson said. "One person was taken to Royal Melbourne Hospital in a critical condition," "Nineteen other people were taken to Royal Melbourne Hospital, Ballarat Base Hospital, Sunshine Hospital and Footscray Hospital, in stable conditions." A Department of Transport and Planning spokesperson said the fog was making it difficult for drivers to see, with pictures sent to The Courier by drivers stuck in the gridlock showing extremely low visibility. "Motorists heading towards Ballarat will be sent off the freeway at Bacchus Marsh where they will need to take a lengthy detour using Geelong-Bacchus Marsh Road into Geelong, then Geelong-Ballan Road," the Department of Transport and Planning said. "Those heading towards Melbourne will be sent off the freeway at Greendale-Myrniong Road to take the Old Western Highway and Pentland Hills Road. "For drivers leaving Melbourne, wider detours should be considered including the Princes Freeway to Geelong then the Midland Highway to Ballarat. Heading north on the Calder Freeway to Kyneton then diverting through Daylesford is another option. "This closure is under the control of Victoria Police. The freeway will only re-open when it is safe to do so. "Real-time traffic conditions are available at traffic.vicroads.vic.gov.au. "The latest public transport information and network status is available at ptv.vic.gov.au or in the PTV mobile app." IN OTHER NEWS: Meet Ballarat's VCE highest achievers of 2023