COPENHAGEN, Denmark (AP) — Danish police said Tuesday that they were closing the investigation into the devastating fire that destroyed more than half of Copenhagen’s Old Stock Exchange, saying nothing points at the blaze being the result of a criminal act.

Despite extensive forensic investigations, review of surveillance and the questioning of a large number of witnesses, “it is not possible to determine the cause of the fire in the historic stock exchange building," said Brian Belling, the Copenhagen police officer in charge of the investigation.

“Our assessment is that we have explored all relevant investigative possibilities in the case,” Belling told a press conference, adding that no one has been charged in the case.

Belling said the video material included hours of footage from inside the Stock Exchange that had not been damaged by the fire. He added that no inflammable liquid has been found.

In the early morning of April 16, a violent fire tore through the 400-year-old building, a major tourist attraction. The blaze toppled its green copper roof and iconic dragon-tail spire. Two days later, a large section of the building’s outer wall collapsed inwards.

As the fire raged, many, including ordinary people, ventured in to rescue artworks and around 90% of the cultural objects were rescued from the building.

One of the hypotheses was that the fire started in connection with the renovation, Belling said.

He said that the fire is believed to have started under the roof, which had been wrapped in scaffolding because of ongoing renovation work to be completed for its anniversary in 2024.

“There is guidance regarding listed buildings when renovating them. It is our opinion that they have been followed to the letter,” Tim Ole Simonsen, a senior member of the Greater Copenhagen Fire Department, told the same news conference. “Then you can discuss whether they are good enough.”

On Sept. 24, King Frederik X of Denmark laid the “foundation stone” within part of a red brick wall that survived the mid-April blaze, marking the commencing of a yearslong reconstruction plan.

The owner of the downtown exchange, the Denmark’s Chamber of Commerce, has said that they will rebuild the landmark, which is considered a leading example of Dutch Renaissance style in Denmark. Construction started in 1615 and it first opened in 1624.

The fire was reminiscent of the April 2019 blaze at the 800-year-old Notre Dame Cathedral in Paris.