Drivers were being warned to expect further delays on Scotland's Forth Road Bridge after a uthorities shut the crossing's southbound carriageway as a safety precaution.
This followed an engineers' routine inspection which uncovered a defect.
Restrictions are likely to be kept in place until the middle of Thursday (December 3) at the earliest.
Only one lane both southbound and northbound will be open until then.
It means that drivers have already suffered "terrible" delays, some of up to two hours.
The disruption has caused substantial knock-on effects on surrounding traffic routes.
Kincardine Bridge and the M90 bore the brunt of the jams on Wednesday (December 2) with contraflows operating on northbound routes.
Motorists suffered typical bridge delays of around 25 minutes at 8.30am.
But one driver heading from Fife who described the experience as "terrible" said he had been in a jam for around two hours.
M90 jams ran back to Halbeath (junction 3), according to Traffic Scotland.
Motorists experienced similar slow-moving conditions past Dalmeny on the northbound M90. The A985 was also packed with commuters.
Amey, the road network firm, says the bridge also has eight other areas where a comparable fault could be found later on.
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