UPDATE: Tasmania police are conducting an investigation into three simultaneous crashes that occurred around 8am.
Acting Sergeant Casey Wood said eight vehicles and a bus were involved in crashes and that there were no serious injuries.
"There were actually three separate incidents, crashes, as a result of that first initial accident," Acting Sergeant Wood said.
"With the first incident, it was in relation to someone that had slightly pulled over on the side of the road. Investigations are still continuing in relation to that crash.
"The second incident was involved due to the wet road and the sun and fog and the third crash was in relation also to those contributing factors.
"Investigations are still continuing at this time to outline what has happened in relation to those separate incidents," she said.
Acting Sergeant Wood said two females were taken to hospital for injuries and said the accident could have been very serious.
"This is why Tasmania Police would like to reiterate that people need to drive to the conditions.
"The roads were wet, and also it was very foggy, and with the sun coming up at that time of the day, it was highly critical to maintain road awareness
"If the roads are wet and there's fog, we really need to slow down and be mindful of other road users as well," she said.
EARLIER: Tasmania Police and emergency services are responding to what they say is a serious multiple-vehicle crash at Longford.
Illawarra Road is blocked between the Bass Highway and Midland Highway and police have asked motorists to avoid the area.
Police said no life-threatening injuries have been reported.
They said nine vehicles were involved, including a bus.
A driver who witnessed the scene said there was an initial collision, and then a second collision due to the thick fog in the area.
"We were driving from Launceston to Longford ... pulled over on the side of the road and just waited for the emergency services to turn up," he said.
"Unfortunately, the bus came up behind us, it was quite foggy, low visibility, bus has seen the whole scene quite late, unfortunately he collided with probably four or five cars that were parked on the side of the road.
"I don't think anyone was hurt."
There have so far been 33 fatalities on Tasmanian roads this year and more than 110 serious crashes compared to 13 deaths to July 4, 2021.
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