A lane closure on the Forth Road Bridge caused by a defect in steelwork has led to severe traffic delays.
The southbound carriageway over the bridge was closed on Tuesday evening after engineers found the problem during a routine inspection.
A contraflow system has been set up on the northbound carriageway but motorists are advised to avoid the bridge if possible.
Commuters who took the route were stuck in queues in both directions, facing long delays during Wednesday morning rush hour.
A full assessment of the fault is to be carried out.
Mark Arndt, from bridge operator Amey, said: “We’ve taken the decision to close the southbound carriageway as a safety precaution after one of our engineers spotted a new defect to a piece of steelwork.
“Unfortunately this defect is located in a particularly hard-to-access area so the full detailed inspection cannot safely be carried out in darkness or during high winds.
“We apologise for the short notice to these essential traffic restrictions and are aware that they will result in very long delays, so our advice is to avoid the Forth Road Bridge and divert via Kincardine or the A9 and M9, use public transport or travel out with peak times.
“We do sympathise with all drivers who face delays, however I’m sure everyone appreciates that safety must come first.”