Police evacuated a hotel and offices connected to the Liseberg Amusement Park and warned households in the area to remain indoors

Stockholm (AFP) - A large fire broke out Monday at Sweden’s largest amusement park in Gothenburg, engulfing a newly built water park in flames, authorities said, with a dozen people sustaining minor injuries.

Police evacuated a hotel and offices connected to the Liseberg Amusement Park in central Gothenburg, and warned households in the area to remain indoors due to smoke.

According to police, 12 people sought treatment at a nearby hospital for minor injuries.

Images from the scene showed exploding fireballs, as flames and several blasts tore up a water slide and a pall of black smoke rose over the city.

“The fire originated at one of the water attractions” located outside the main building housing the water park “and then spread throughout the building”, Liseberg said in a statement.

The cause of the fire was unknown, however police said the incident was currently being investigated as a “workplace accident”.

The water park is part of an expansion project for the amusement park and was set to open later this year.

News agency TT said earlier reports estimated the cost of the new water park at 1.2 billion kronor ($115 million).