Police shut the main route out of Abu Dhabi city during morning rush hour on Thursday due to a multiple car accident on Sheikh Zayed Road.
Several ambulances and police cars raced to the scene opposite Raha Mall on Sheikh Zayed bin Sultan Street at around 6.30am.
Abu Dhabi Police has yet to release any details, but it is believed the crash involved a bus, which was left badly damaged, according to witnesses, in addition to several cars.
The incident resulted in long tailbacks with standing traffic, leading police to shut the road to cars at the exit before Sheikh Zayed Bridge for a time.
Police posted a tweet to say traffic was back to normal by 8.55am.
The wreckage of the bus was still at the scene two hours later at 8.30am, as a helicopter hovered overhead and traffic remained backed up behind.
Motorists already on the road took to social media to warn others to use an alternative route as some commented that they had been stuck for an hour.
Writing on The National's Facebook page, one motorist said he was still stuck in traffic, almost an hour and a half after setting out on Salam Street at 7am.
"It's now 8.20am and I'm still stuck at the beginning of Sheikh Zayed Bridge where Khalifa University is.
"It's crazy. I've never seen any kind of traffic jam like this in Abu Dhabi before."
Cars were rerouted in the direction of Sheikh Zayed Grand Mosque, towards Khaleej Al Arabi Street, resulting in tailbacks on Salam Street. Google Maps showed congestion going all the back from Sheikh Zayed Bridge to Reem Island.