The man, who is a 43-year-old citizen of the central African country of Burundi, is suspected of having taken part in illegal intelligence activities in central Sweden.
He was arrested on Monday morning in Örebro, and faces court on Wednesday for his remand hearing, according to the local paper Nerikes Allehanda.
According to the prosecutor, Ronnie Jacobsson, the alleged spying took place between July 1st 2010 and May 1st 2011.
However, Jacobsson was not able to disclose any further information at such a delicate stage of the investigation.
“Before the remand hearing on Wednesday, I cannot provide any additional information as it may damage the investigation,” said Jacobsson to the paper.
The suspected man was taken into custody as it was feared that he would destroy or manipulate potential evidence that could prove his involvement, if he was released.
Police took no chances that could have allowed the man to escape punishment or prosecution, wrote the paper.
The 43-year-old is a citizen of Burundi, and a resident of Örebro, wrote the TT news agency.
The remand hearing will be held on Wednesday morning at the Örebro District Court.