Part of the A27 in Chichester was closed for six hours on Friday night (November 29) because of a large oil spill which followed a collision, according to Sussex Police.
Police said officers were called just before 9pm to an accident on the A27 before the Portfield roundabout.
On Twitter in the early hours of Saturday morning, Chichester Police wrote: "The road remains closed awaiting Highways England's assessment of the road surface. Please find an alternative route."
Police later confirmed that the road had been reopened by 3am.
Providing an update today (Tuesday, December 3), a police spokesman said: "The road was closed because of an oil spill and there were no major injuries.
"It was dealt with by Highways England."
According to an eyewitness, the collision involved a car and a tractor. Traffic reports, at the time of the incident, said it happened on the A27 westbound from A285 (Halnaker / Petworth turn off) to A285 Portfield Way.
A number of motorists reported on social media that they were stuck in traffic for more than three hours.
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