Around 400 metres of road is covered in glue on the A76, near Sanquhar, after a lorry overturned.
The road is expected to be closed for several hours.
The current diversion is 50 miles long.
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An undercover Trading Standards tobacco and alcohol sales operation has shown that local businesses are refusing to sell to underage people.
The Jim Clark Rally is changing the format, this years event on Sunday 31st May will run on private Forestry Commission gravel roads.