The arrest of the 29 year old man has angered Russia, which demanded his swift release Wednesday after calling in Sweden’s ambassador to discuss the case.
The Stockholm District Court, however, ruled there was enough evidence against the 29 year old to keep him detained.
Under Swedish law, a detention order must be renewed every two weeks.
The accused spy has denied the charges, and the court’s decision led the Russian Embassy in Stockholm to reiterate the country’s request that the 29 year old should be released, calling the accusations ”baseless.”
The Russian national was working as a visiting researcher at the University of Agricultural Sciences in Uppsala, when he was arrested on February 15th.
Security police have refused to disclose what country he is accused of working for, or elaborate on the nature of the espionage allegations.
The Swedish government has said it cannot interfere with the investigation because it is a police matter.
Prosecutors have until March 30 to either file charges against the Russian national, or ask that he be held for another two-week period.