STOCKHOLM — A powerful explosion occurred outside the Danish Tax Agency in the capital, Copenhagen, shattering windows, damaging the building and slightly injuring one person.

Chief Police Inspector Jorgen Bergen Skov told a news conference Wednesday that the explosion took place Tuesday evening in an area near the Nordhavn S-train station.

Police believe the explosion was not an accident.

“It is still too early to tell who might be the perpetrators, but we take this incident very seriously and have launched an extensive investigation. We neither can nor will accept an act like this one,” Skov said.

Police said one person who was standing near the Nordhavn S-train station was lightly injured by debris and received treatment in an emergency room.