Six people died and 19 others were injured when a bus crashed into a lorry in Abu Dhabi on Thursday.
The collision occurred on the Dubai-bound Sheikh Zayed bin Sultan Street, opposite Al Raha Beach, at about 6.30am.
Police said that Falcon Eye surveillance cameras showed the accident was caused by "reckless behaviour" a motorist in a white sedan, who slowed in front of a lorry to take an exit.
A second lorry was travelling close behind and stopped, before the bus crashed into the back of it.
Police released footage, which was slowed down in parts, that showed the four vehicles involved.
The first lorry driver was forced to brake suddenly when the white sedan slowed down at the exit.
The second lorry stopped in time to avoid a collision but the bus smashed into the back of the second lorry.
Other cars and buses are then seen braking and changing lanes to avoid the collision.
Lt Col Mohammed Al Hosani, head of the Traffic Investigation Department, said officers and paramedics worked quickly to take the injured to hospital and remove the damaged vehicles from the motorway.
Police closed the main route out of the capital, from the exit before Sheikh Zayed Bridge, to help those hurt and redirect traffic. The crash caused long tailbacks with standing traffic but police said traffic was back to normal by 8.55am.
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.
Lt Col Al Hosani urged motorists against "irrational and irresponsible behaviour" that could cause fatal accidents. He also reminded motorists to adhere to traffic signs and speed limits.