A landslide has forced the closure of one of the main roads near Loch Lomond following more heavy rain.
The A83 Rest and Be Thankful Tarbet to Campbeltown road was closed at around 7.20am on Thursday after more than 100 tonnes of material fell on the route.
Strathclyde Police are dealing with the closed road between the B828 and A815 turnoffs and as debris is being cleared.
The police force said the road would probably not reopen until Thursday afternoon, however First Minister Alex Salmond revealed at Holyrood on Thursday that the A83 may be closed for 24 hours.
Mr Salmond said: "Engineers are onsite as we speak but there can be no clearance operation until the water has subsided and a risk assessment of any further slippage is carried through.
"The local radio stations have been informed of the situation, a diversion route has been put in place and communicated to the public.
"Details have also been communicated to the relevant ferry companies. We can't as yet confirm when the road will reopen. We expect it may be closed for up to 24 hours."
Diversions via the A83 Inveraray, A819 Dalmally, A85 Tyndrum and A82 Tarbet have been put in place after the landslide occurred and closed the road in both directions.
The landslip is understood to have occurred after more than 36mm of rain fell in the area in the last 24 hours, and 29.8mm the day before.
Normally, the monthly average for rainfall in Argyllshire is around 239mm, meaning more than a quarter of the month's expected rain fell in two days.
Transport Scotland said it is working with police and Argyll and Bute Council in response to the incident, but diversions mean an extra 26 miles has been added to journeys.
A spokesman said: "A team of engineers is currently on site assessing the situation, but we know that up to 100 tonnes of material has already fallen onto the road and there is still movement being recorded by the operating company.
"The clearance operation will get under way once the water has subsided and a risk assessment of further slippage is made.
"Our absolute priority is the safety of motorists and we appreciate their patience as this matter is dealt with as a matter of urgency."
Michael Russell, MSP for Argyll and Bute, said the road closure would have an impact on the local economy.
He added: "I have been in touch with the transport minister who assures me that everything possible is being done to clear the site and ensure that the road is safe and reopened as quickly as possible.
"It is imperative that the road is reopened as soon as possible as the alternative routes are lengthy, present huge logistical problems and disadvantage many Argyll businesses that rely on the passing trade that the traffic on this route provides."
This is the third time in recent years that the A-road has been forced to close by a landslide after similar landslips in 2007 and 2009.