Parts of the M4 were closed earlier due to an oil spill, just before rush hour traffic was due to hit roads.
Traffic officers spent three hours dealing with the hydraulic oil spill on the westbound carriageway between junction 29 for Cardiff and 28 for Tredegar Park, BBC News reported.
The incident occurred at around 4pm on Friday afternoon, leaving commuters to deal with long queues.
Traffic Wales reported that the spill caused 13 miles of tailbacks to Magor, and traffic also built up eastbound.
Disgruntled social media users took to Twitter to complain. Double world champion cyclist Becky James was among those who tweeted about being stuck in the traffic.
On not such a good note, I am currently parked on the m4! #traffic— Becky James (@BecksJames) January 30, 2015
The two lanes were closed while the spillage was cleared.
The parts affected by the spill have since re-opened.Reuse content