Investigations into a large fire on Abu Dhabi Breakwater on Tuesday morning are under way, a police official said.
The blaze started at about 11.35am and appeared to be coming from behind the Fairmont Marina Residences - currently under construction.
A plume of thick, black smoke billowed across the skyline, briefly obscuring the hotel.
Motorists were seen pulling over to watch the smoke and construction workers on the Corniche also paused work.
Fire trucks and police patrols attended the scene to extinguish the blaze and begin investigations into the cause.
Police said the fire began in an area where cables and scrap wood are stored.
Brig Gen Mohammed Al Ketbi, director-general of civil defence, called on companies to ensure their equipment and materials are correctly stored, according to health and safety regulations, to prevent such incidents.
He said all storage areas should also be fitted with fire extinguishers.
The fire across from Marina Mall was one of two tackled by civil defence on Tuesday.
The second broke out in a store room containing old air conditioning units near the Chinese market in Mafraq Industrial Area at 12.25pm.
No injuries were reported in either fire.