Firefighters in Sweden were struggling for the second day on Tuesday to put out a blaze at a water park that's under construction at one of the country’s biggest amusement centers. One park employee is missing and 16 people, mainly workers, were slightly injured.

Authorities could not say what had caused the fire at the Oceana water park in the popular Liseberg amusement complex in Goteborg, Sweden’s second-largest city. The fire broke out on Monday and spread over several water slides and the pool area.

Svante Carlsson of the city's fire department said his firefighters have gotten the fire under control on Tuesday. There was "extensive damage and some parts of the structure have collapsed," he said, adding that he expects his crews "to be on the scene for some time."

FIRE BREAKS OUT AT WATER PARK UNDER CONSTRUCTION AT POPULAR SWEDISH THEME PARK

A nearby hotel and office facilities were evacuated. Police earlier said they were investigating the blaze as a workplace accident and a case of "gross public negligence."

Quelling the blaze had been made difficult because of the risk of collapse, firefighters said, adding there still were pockets of fire burning.

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Oceana, which had been scheduled to open this summer, is to include an indoor swimming area of almost 7,176 square yards and a 4,780-square yard outdoor swimming facility.

The water park has said that up to 1,750 guests can visit at a time. Liseberg, which opened in 1923, is a popular tourist destination with some 3 million visitors a year.