DUBAI (Reuters) - A fire broke out on Friday on a yacht under maintenance off the Dubai coast, caused by an engine malfunction, the local authorities said. No casualties were reported.

Thick black smoke was visible from the Dubai coastline - including a beach near the ultra-luxurious Burj al-Arab hotel - causing concern that it could be coming from an oil tanker or a passenger ship, as tensions run high between Iran and the United States.

According to two Reuters witnesses, the smoke dissipated about an hour after it was first reported in social media postings.

The U.S. administration last year blamed Iran for explosions that damaged several oil tankers off the United Arab Emirates (UAE) coast. Tehran denied the accusation.

The government media office of Dubai, one of the seven members that make up the UAE federation, said in a statement that the fire started on a yacht that had been taken out for a test run.

“The blaze appears to have been caused by engine failure and fuel leakage,” it said. It was brought under control by the Dubai civil defence force, which safely evacuated three people who were on board, it added.