Prosecutors have filed charges against two suspects in relation to the detonation of an explosive device left under a car in the city of Tornio, Lapland last August.
One of the defendants will also face a second charge of committing an explosives offence.
The vehicle, a blue Volkswagen Transporter van, had been hired for use by the Finnish Border Guard at the time of the incident.
The explosion took place in the city's residential neighbourhood of Pudas, an area that contains apartment blocks.
Both the police and the prosecutor have tried to establish a motive during the course of the pre-trial investigation. Police ruled out terrorism in the days following the explosion.
"So far, no clear motive has emerged. The investigation will continue until the main hearing at the district court, which will be held in due course," the prosecutor's office said.
There were no injuries in the explosion and no significant damage was caused, police said.
Both defendants have been taken into custody during the course of the pre-trial investigation, but they are not currently being detained.
They have both denied involvement.