A fire broke out on Sunday at the Haramain high-speed train station in Saudi Arabia's coastal city of Jeddah.
There were no immediate reports of injuries and emergency services continued to battle the flames in the afternoon.
"The civil defence is putting out a fire that broke out at a station in Suleimaniya ... no injuries have been recorded as of yet," the General Directorate of Saudi Civil Defence said on Twitter.
Videos shared on social media showed plumes of black smoke billowing from the building's roof.
Opened in September 2018, the $7.3 billion (Dh26.8bn), 450-kilometre Haramain Railway links the two holiest cities in Islam, Makkah and Madinah , with Jeddah.
Trains running on the line can reach speeds of 300 kilometres per hour.
In 2011, the kingdom signed a deal for a Spanish consortium to build the rail track, supply 35 high-speed trains and handle a 12-year maintenance contract.
The kingdom is boosting its infrastructure spending and expanding its railways, including a $22.5bn metro system under construction in the capital, Riyadh, as it seeks to diversify its oil-dependent economy.
