A huge fire ripped through a luxury Dubai hotel Thursday night, injuring 16 people, just a few hours before the emirate celebrated the new year with a spectacular fireworks display nearby.

The Address Downtown hotel, which is a few blocks from the iconic Burj Khalifa, the world's tallest tower, was engulfed in flames across several floors as sirens wailed and helicopters hovered overhead, witnesses said.

Dubai's police chief said all the residents of the five-star hotel had been evacuated from the scene of the blaze, the cause of which was unknown and which had still not been extinguished some four hours after it broke out.

"All the residents are out," General Khamis Matar al-Mzeima said.

"Until the fire is put out, we will not have information on what caused it," he added.

"At least 14 people have been slightly injured, along with one medium injury, and a heart attack case registered due to people pushing" amid the smoke, the media office tweeted.

Witness Raphael Slama told AFP the fire started at around 9:30pm (1730 GMT) and rapidly spread upwards across dozens of floors.

An AFP photographer at the scene said "it began in the middle of the hotel, then went down like lightning before shooting up again."

"People in the vicinity began to run in panic to get away from the area," he added.

Kumar, an Indian resident in Dubai who was near the hotel with his wife, told AFP: "We saw fire coming out of the top storeys two hours before midnight and people began screaming and running away from the hotel."

"What was strange is that the fire was disappearing and then reappearing again," said Mohammed al-Majed, a Saudi tourist who was at the restaurant around a kilometre (mile) away. "It was mainly concentrated in the middle of the building."

"We were worried about casualties and afraid the celebrations would be cancelled."

A video circulating on social media showed anxious shoppers at the huge nearby Dubai Mall as they rushed to get out, with a woman shouting: "Folks don't run... don't panic".

Another witness who asked not to be named and was near the hotel area told AFP that New Year's Eve event organisers and security personnel "started panicking and were screaming and ushering people" into the nearby Dubai Mall, one of the world's largest shopping centres.

"Half an hour later, they told us to get out of the mall because they were closing it down, he said, adding that people began running out.

"There were a lot of screams... There were a lot of people who fainted and there were many ambulances" as well as "crowding and pushing."

The government tweeted that the hotel fire erupted on the 20th floor and affected only the outer facade of the building.

"Four firefighting teams have been deployed" to fight the blaze, it added.

Authorities said earlier Thursday that they had deployed thousands of security personnel to ensure visitors and residents could enjoy the New Year's festivities safely.


History of skyscraper fires

The hotel is one of the tallest buildings in Dubai, with seven lounges and restaurants as well as a beauty spa, according to its website.

A spectacular fireworks display kicked off as planned at midnight (2000 GMT), beginning at the 828 metre (2,700 foot) high Burj Khalifa before spreading across the skies of the cash-flush city above thousands of cheering spectators.

Lasers flashed through the skies over the chic district surrounding the tower, even as smoke was still billowing from the blaze nearby.

"From @BurjKhalifa to the world: Happy New Year 2016," said the Dubai government media office on Twitter.

Dubai's futuristic cityscape is famous for its hugely varied skyscrapers.

In November, a massive blaze engulfed three residential blocs in central Dubai and led to services on a metro line being suspended, although no one was hurt.

In February, a huge fire gutted one of the emirate's tallest buildings, destroying luxury flats in the Torch tower and triggering an evacuation of nearby blocs in the Dubai Marina neighbourhood -- a district popular among expatriates.

And in 2012, a huge blaze gutted the 34-storey Tamweel Tower in the nearby Jumeirah Lake Towers district. It was later revealed to have been caused by a cigarette butt thrown into a bin.